Modern Teaching Aids for College Chemistry -- Portable Video Recording Systems, New Uses for Films, Computer Assisted Instruction

REPORT RESUMES

ED 011 121 SE 002 770 MODERN TEACHING AIDS FOR COLLEGE CHEMISTRY -- PORTABLE VIDEO RECORDING SYSTEMS, NEW USES FOR FILMS, COMPUTER ASSISTED INSTRUCTION. 5Y- LIPPINCOTT, W.T. BRASTED, R.C. ADVISORY COUNCIL ON COLL. CHEMISTRY REPORT NUMBER ACCC- TAC -SER- PUB -18 PUB DATE DEC 66 EDRS PRICE MFSO.25 HC -$2.24 54P.

DESCRIPTORS- *AUDIOVISUAL AIDS, *COLLEGE SCIENCE, *CHEMISTRY. *CONFERENCE REPORTS, *INSTRUCTION, BIBLIOGRAPHIES, COMPUTER ASSISTED INSTRUCTION, EDUCATIONAL TELEVISION, FILMS, PROJECTION EQUIPMENT, TELEVISION, ADVISORY COUNCIL ON COLLEGE CHEMISTRY, STANFORD UNIVERSITY

RESULTS OF A 1966 CONFERENCE ON TEACHING AIDS FOR COLLEGE CHEMISTRY ARE SUMMARIZED IN THIS REPORT. MAJOR SECTIONS OF THE REPORT ARE (1) PORTABLE TELEVISION TAPE RECORDING SYSTEMS,(2) FILMS AND FILM LOOPS, AND (3) COMPUTER- ASSISTED INSTRUCTION. A SUMMARY OF PRESENT AND POTENTIAL INSTRUCTIONAL APPLICATIONS FOR EACH MAJOR TYPE OF MEDIA IS PRESENTED. INFORMATION ABOUT THE PURCHASE, USE, AND MAINTENANCE OF EQUIPMENT IS PROVIDED. THE SECTION ON EDUCATIONAL TELEVISION CONTAINS INFORMATION ABOUT CLOSED CIRCUIT TELEVISION EQUIPMENT AND THE BASIC PRINCIPLES OF VIDEO TAPE RECORDING. FILM LECTURE- EXPERIMENTS, SINGLE CONCEPT FILMS, FILMS THAT ILLUSTRATE THE STRUCTURE AND OPERATION OF INSTRUMENTS, FILMS FOR OUT- OF-CLASS VIEWING, FILMS COORDINATED WITH OTHER TYPES OF MEDIA, ANCILLARY MATERIALS FOR FILMS AND TAPES, AND FILMING TECHNIQUES ARE CONSIDERED IN THE SECTION ON EDUCATIONAL FILMS. THE SECTION CONCERNING EDUCATION FILMS ALSO INCLUDES A COMPREHENSIVE GUIDE TO SOURCES OF VISUAL AIDS, A DESCRIPTION OF THE FEATURES, SOURCES, AND COSTS OF VARIOUS TYPES OF PROJECTION EQUIPMENT, AND A DISCUSSION OF PROJECTION :SCREENS. THE SECTION ON COMPUTER- ASSISTED INSTRUCTION INCLUDES A GENERAL DESCRIPTION OF NECESSARY EQUIPMENT, AN EXPLANATION OF A TYPICAL PROGRAM, AND THE APPLICATION OF COMPUTER- ASSISTED INSTRUCTION TO THE TEACHING OF CHEMISTRY. REFERENCES FOR EDUCATIONAL TELEVISION AND COMPUTER- ASSISTED INSTRUCTION ARE APPENDED. THIS DOCUMENT IS ALSO AVAILABLE FROM THE ADVISORY COUNCIL ON COLLEGE CHEMISTRY, DEPARTMENT OF CHEMISTRY, STANFORD UNIVERSITY, STANFORD, CALIFORNIA 94305. (AG) MODERN TEACHING AIDS FOR COLLEGE CHEMISTRY

A Project Of The TEACHING AIDS COMMITTEE of the ADVISORY COUNCIL ON COLLEGE CHEMISTRY au, , wisp,777",411,011 tit , U.S. DEPARTMENT Of HEALTH. EDUCATION a WELFARE OFFICE Of EDUCATION

THIS DOCUMENT HAS KEN REPRODUCED EXACTLY AS RECEIVED FROM THE PERSON OR ORGANIZATION ORIGINATING 11 POINTS Of VIEW OR OPINIONS

STATED DO NOT NECESSARILY REPRESENT OFFICIAL OFFICE OF EDUCATION POSITION OR POLICY MODERN TEACHING AIDS FOR COLLEGE CHEMISTRY PORTABLE VIDEO RECORDING SYSTEMS NEW USES FOR FILMS COMPUTER ASSISTED INSTRUCTION A Project Of The TEACHING AIDS COMMITTEE of the ADVISORY COUNCIL ON COLLEGE CHEMISTRY

Contributors: W.R. Barnard, Ohio State University; R. C. Brasted, University of Minnesota; W. B. Cook, Advisory Council on College Chemistry; E. L. Haenisch, Wabash College; R. N. Hammer, Michigan State University; J.J. Lagowski, University of Texas; W. T. Lippincott, Ohio State University; W. T. Mooney, El Camino College; B. E. Norcross, State College, N. Y. at Binghamton; W. H. Slabaugh, Oregon State University; J. A. Young, King's College.

SERIAL PUBLICATIONNUMBER 18 DECEMBER 1966 ADVISORY COUNCIL on COLLEGECHEMISTRY Department of Chemistry, Stanford University, Stanford,California 94305 The Advisory Council on College Chemistry is anindependent group of chemists interested in how improvement and innovation inundergraduate chemistry curricula and instruction can be effectively implemented at the national level. The Councilcollects and disseninates information through the activities of standing committees onFreshman Chemistry, Curricula and Advanced Courses, Teaching Aids, Teacher Development, Science forNon-Science Majors, Junior Colleges, Resource Papers, and an Editorial Committee.Additional ad hoc groups act as necessary. The Council hopes toprovide leadership and stimulus for imaginative projects on the part of individual chemists. The Council is one of a group of collegiate commissionssupported by grants from the National Science Foundation. The Council cooperates in intercommission activities. OFFICERS and STAFF L. C. King, Chairman; W. H. Eberhardt, University; William F. Kieffer, '67, The Col- Vice-Chairman; W. B. Cook, Executive Direc- lege of Wooster; L. Carroll King, '69, North- tor; A. F. Isbell, Senior Stag Associate. western University; Richard J. Kokes, '67, COUNCIL MEMBERS: Bobbin C. Ander- The Johns Hopkins University; Elwin M. Lar- son '87, The University ofTexas; Cordon M. sen, '68, University of Wisconsin; 'W W. T. Lip- Barrow, '68, Case Institute of Technology; pincott, '67, The Ohio State University; How- 0. Theodore Benfey, 68, Earlham College; ard V. Malmstadt, '89, University of Illinois; Henry A. Bent, '69, University of Minnesota; William T. Mooney, Jr., '69, El Camino Col- Robert C. Brasted, '69, University of Min- lege; Leonard K. Nash, '87, Harvard Univer- nesota; Melvin Calvin, '67, University ofCali- sity; Melvin S. Newman, '68, The Ohio State fornia; J. Arthur Campbell, '68, Harvey Mudd University; Charles C. Price, '69, University College; William H. Eberhardt, '68, Georgia of Pennsylvania; Charles N. Reilley, '68, Uni- Institute of Technology; Harry B. Cray, '69, versity of North Carolina; Frederich W. California Institute of Technology; Edward Schmitz, '67, New York City Community Col- L. Haenisch, '67, Wabash College; David N. lege; Glenn T. Seaborg, '67, Atomic Energy Hume, '69, Massachusetts Institute of Tech- Commission; Robert I. Walter, '69, Haverford nology; Emil T. Kaiser, '09, The University of College; Peter E. Yankwich, '88, University of Chicago; Michael Kasha, '69, Florida State Illinois; Jay A. Young, '68, Kings College. ExiscutiveCOMMitiel.

xlloz,trlietroirmlaz. PREFACE

This report is the result ofa writing confer- SONY Corporation, Mr. David Thowas of ence held at Stanford University in late July and Reeves Engineering and Mr. William Justus of early August of 1966. Itwas conceived at a con- the Telecommunications Center at Ohio State ference onnew teaching aids sponsored by the University, for their, invaluable advice during Advisory Council and heldat the MIT Science and after the writing conference. Acknowledge- Teaching Center in March1966. At that time, it ment also is made to Mrs. William B. Cook and became apparent thatvery recent technological her staff at AC3 headquarters aidto Mrs. Sue developments in the audio-visualsindustry had Adler of Ohio State University for eir consid- made available relativelyinexpensive, especially erable assistance in theprepar ition of the manu- reliable, and uncommonlyeasy to operate film script. Photographs of television monitorswere projectors, portable videotape recorders and made by Mr. Dave Eelby of the Teaching Aids other hardware, all of which appearedto offer Laboratory at Ohio State University. unusual potential for improving college chem- The Teaching Aids Committee will istry instruction. Because most participantsat continue in its efforts to develop materials to exploit the the MIT conferencewere unfamiliar with the new hardware and its potential, it was suggested capabilitiesof new audio-visual techniques. Every effort will be made to bring these that a rather detailedsummary of these new de- new capabilities before the chemical education velopments and of their applicationsto chemis- com- try instruction be prepared and made available munity and, when possible, to distribute samples 0 to college chemistry teachers. of the developed materials to interested college chemistry teachers. We alsoare interested in Mr. Robert Barnard, then at Montana State learning of activities or programs which employ University and novaat Ohio State University, new teaching aids or techniques so we fan fa- assumed the heavy burden of gathering infor- cilitate the spread of novel ideas and applica- mation on films, film hardware, andon video tions. In addition, we encourage inquirieson tape systems. He, in collaboration with Professor these matters and will appreciate assistanceon E. L. Haenisch, W. H. Slabaugh and W. T our several projects designed to improve college Mooney, is largely responsible for the section of chemistry instruction by the effectiveuse of the report on films. Professors W. B. Cook,R. N. audio-visual aids. Hammers W. T. Lippincott, and B. E. Norcross The Teaching Aids Committee of AC, assembled and wrote the sectionon video systems. Professors J. J. Lagowski, and J. A. Young J. A. CAMPBELL contributed the sectionon computer-assisted in- W. B. Coox struction. Professors W. T. Lippincott and R. C. E. L. HAENISCH Brasted read and edited the entirereport. W. F. KIEFFER The members of the writingteam are in- H. V. MALMSTADT debted to the consultants, Mr. John Floryof J. A. YOUNG Eastman-Kodak, Mr. Don Horstkorta of the W. T. LIPPThicorr, Chairman 101

animated growt Growing zincdendriteswith accompanying film, "Metal Crystal sequence.Photographed from color for Metals. in Action" producedby American Soci'ety

ofh.*Piaan, TABLE OF CONTENTS 1 INTRODUCTION...... Portable Video Tape Recording Systems . 5 TV in Chemistry Instruction . . . 5 New Capabilities and New Uses . 5 Preparation of Video Tapes . . . . 7 Closed Circuit Television Systems . . 7 The basic video recording installation . 9 Expansion of the basic video recording installation 9 Distribution of television signals . . . 11 Lighting . . . . 11 Maintenance 11 Video tape...... 11 Large screen television projection . . 12 Color television. . . . . 12

Principles of Video Tape Recording ...... 13 Role of TV Cameras and Accessories . . 13 Video Tape Recording . . . . . 13 Video recorder heads . . . . 14 Rotating recorder heads. . 14 Image sharpness in video recordings . . 14 Editing, Interchangeability and Standards . . . 15

Films and Film Loops. . . . 17 New Uses for Films . . . . 17 Some specific examples. . . . . 19 Auxiliary materials for films and tapes . . 23 Sources of Chemistry Films . . . . 24 Film directories. . . 24 Other film sources . . . . . 25 Equipment: Its Availability and Uses . 26 Film types. . . . . 26 Projectors. . . . . 27 Sound characteristics of film . . . 29 Film costs. . . . . 31 Cameras and lenses...... 31 Still projection systems . . 31 Utilization of Projected Materials . . . . 32 Projection screens . . . 32 ComputerAssisted Instruction . . 37 Equipmeat. . . . 37 Programs...... 38 The Use of ComputerAssisted Instruction in Chemistry . 41 Laboratory. . . 0 41 Tutorial assistance. . . . 42 Evaluation of student ability and progress . . 42 Incorporation of other material . . . 42 Summary...... 43 References and Footnotes ...... 45 IP'

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.10 .11111 INTRODUCTION The knowledge explosion, which for chemis- ter responds in seconds with a new spectrum try at this writing brings a doubling of the total which is a close fit but not an exact fit. Again amount of published chemical information every the chemist increases the bond angle in the com- seven and a half years, and which provides a puter program and requests still another spec- continuous, exciting and enriching challenge for trum. This time the fit is even closer. chemistry teachers who remain intrigued with Without arguing the pros and cons of whether their subject, has created the conditions fora changes in parameters other than the bond angle major breakthrough in the art and science of might give a similar fit for the computergener- teaching. ated nmr spectrum, the profound message here is Last year a Nobel Laureate sitting in his of- that the classroom teacher now has available to fice in California lectured to a class of chemistry him computing capability having incredible students in Montana. As he wrote and drew memory and able to display its results in numeri- formulas on a pad in front of him, the students cal or in graphical form or even as a moving read his words from a projection screen at the image. front of their classroom. Whena student had a It is mechanical developments such as the question, he pressed a button and the professor, Blackboard-by-Wire, the Data Phone with Voice receiving the signal, immediately acknowledged Writer, the portable television tape recorder, the it, listened to the question and responded. Both cartridge-loading movie projector, the shared- the students and the professor were thrilled by time computer with terminals located in class- the experience. Needless to say the teaching- room which have created the conditions for learning interaction proceeded with unusual revolutionary innovation in teaching and learn- efficiency. ing processes. The examples cited above are but Earlier this year an engineer demonstrating three of many that could be given. newly developed television tape equipment ob- Within six months, and at a cost to his institu- tained permission to tape a chemistry class in tion of not much more than his own yearly sal- session. During the lecture the instructor ignited ary, a chemistry instructor could have at his a balloon containing hydrogen. After class some disposal: students asked to see a replay of that portion of The capability to insert into his lecture with the tape. The engineer while slowing down the the push of a button a 30 second or longer motion suddenly stopped it on one frame and segment of film which illustrates precisely there, in perhaps the first stop-action from tape the point under discussion, in color, in mo- replay in a chemistry classroom, was the image tion, and accentuated by pertinent filmed of the balloon one side a bursting mass of techniques such as close up, time lapse, flames, the other side still intact. slow motion, or animation. Such filmseg- A chemist at Bell Telephone Laboratories, ments could be reversed, re-run, and any teaching other chemists some uses of computers, number could be shown in a lecture all shows how the instrument can be programmed of this via push button control in the hand to reproduce the nuclear magnetic resonance of the lecturer. spectra of some cycloalkanes. He notes, how- The opportunity to prepare, perhaps only ever, that the spectrum of one strained com- hours before use, a television tape of anex- pound does not correspond to the computer- periment which students could never see generated spectrum. Suspecting that perhaps otherwise. By replaying the tape, the class the HCH bond angle is incread in this sub- could not only see the experiment as itwas stance, he asks the computer to give him the performed, but they could make observa- nmr spectrum for this compound if, while all tions, collect data from their seats, and, as other parameters remainconstant, a slight a group, discuss the results and arrive at change is made in the bond angle. The compu- conclusions. As with films, the techniques

1 4111

slow-motion, time- morerewarding, much morefoolproof, and such as magnification, than were efforts with lapse photography would bereadily avail- much less time consuming available in the past. able and could be easilyused by the in- equipment commonly student assist- It is for those who would usethese new tech- structor as he and perhaps a explore some of the al- ant prepare the tape. niques and who would number of teaching innovations A library of single conceptfilm loops pack- most unlimited for immediate they make possible thatthis report has been aged in cartridges and ready three areas in viewing simply by insertingthe cartridge prepared. Its content is limited to developments have into a suitable projector.This library of film which recent technological loops might be located inthe instructor's created unusual new potentialfor college chemistry instruction. These areas are: office or in the library.Students having difficulty with a concept canbe handed the Portable TV tape recording systems. appropriate cartridge andasked to view Films and film loops. Computer-assisted instruction. the film as often as theywish. Such viewing The first section of each partof the report is can bedone in a study carrel or in asmall assignments of material a summaryof present and potentialinstructional quiet area. Home technologi- where motion, color, or timeis important applications in the light of the new borrow the cal capabilities. The secondsection gives infer- can befilmed and students can how to use it, film cartridges as theyborrow books on mation regarding equipment, where to buy it and, whenpossible, how to reserve. section, no effort has A library of film loops onlaboratory tech- maintain it. In the second inexpensive projectors been made to list allmanufacturers and all items niques for use in listed are, in general, located in the laboratory.Similar films of equipment. Materials of instruments can those with which somemember of the writing showing the operation The primary aim in be placed in projectorsand located beside team has had experience. instruments. The results this section is to informchemistry teachers of therespective available and to provide would be a saving offaculty time on rou- the new equipment them with sufficientbackground information to tine laboratory matters. about the pur- A lecture table,digital voltmeter with a make an intelligent judgment basketball score board. chase and use of such equipment. read-out like a small The first section of Part I on TV This would be equippedwith probes which TV systems. ex- tape recording systemsis largely a summaryof would enable the instructor to measure have used TV in perimental parameters such astemperature, the experiences of those who chemistry instruction. Itincludes the findings of voltage, pH, conductivity, vapor pressure. television tape Lecture experiments, asfor example the the Teaching Aids Committee the voltage of a project conducted duringthe spring and sum- effect of concentration on In this project, portable TV tape galvanic cell, could beperformed by the in- mer of 1966. the chemistry departments structor withstudents collecting and work- systems were sent to and universities ( MichiganState ing up data at their seats. at five colleges capabilities already is in opera- University, Montana StateUniversity, Ohio Each of these University and Wa- tion in colleges.Nearly all are beingused in State University, Stanford bash College) where staffmembers made tapes chemistry classrooms.Films, for the uses indi- and more are being of various chemically interestingphenomena cated, now are available of the tapes pro- developed. The hardware, inmost cases,is and equipment. An evaluation moderate costs and is reduced was made by severalmembers of the readily available at of 1966. markably easy to use and tomaintain. While Teaching Aids Committee in August I was prepared instructors will find ittakes time to produce The hardware section of Part equipment, by a writing team ofchemists with assistance quality materials with this new and pro- those who have tried agreethat the work is far and advice from television engineers

2 L 111 ducers from the industry and from theuniver- siderably more complex. Such lessons would sities as acl,nowledged in the Preface. The writ- force the student to think his way through the ing team has madeevery effort to give an accu- problem presented, often allowing him altera- rate but elementary presentation of the princi- tive routes to solutions or permitting him to ples of TV tape recording. Unfortunately, the move some distance along a non-productive field of portable TV tape recording isso new path before bringing him back to a potentially that consensus among the experts often is dif- productive one. ficult to obtain. Therefore, it becamenecessary While computers undoubtedly will be used in to choose among alternatives on certain points instruction in numerous other ways, our experi- in this section. Hopefully, these choices will not ence at present is insufficient to report intelli- prove an inconvenience. gently on these. Nevertheless, projects to ex- Also included in this section is a listing of the plore the uses of computers as in class aids items needed in a basic TV recording installa- ( c.f.Bell Telephone example given earlier ) tion and suggestions for expanding the TV capa- and to prepare some computer-animated films bility. are underway and, hopefully, will be the sub- Films.The first section on films summarizes ject of a subsequent report. some new uses of films and film loops and in- Teachers may well ask if they must become cludes the results of several film preparation pro- audio-visual aids experts and thereby dilute their grams sponsored or stimulated by the Teaching subject matter competence. Those who have Aids Committee. During the spring and summer tried these new techniques believe that they not of 1966, approximately 15 film loops illustrating only enhance the efficiency of presentation but various applications at all undergraduate levels they also enrich the learning process, thereby were prepared. Some of these are original films, increasing the quality of instruction. others were made by extracting footage from ex- The top priority problem in chemical educa- isting films. The film preparation programs are tion today is to discover how to develop chem- continuing to produce sample loops which will ists who have in their minds a much larger body be available on request. of chemical knowledge and greater facility in its Also included in this section are lists of film use than chemists have had in the past. Without sources and sources of film reviews. this the research of the future will be severely In the hardware section, an effort has been limited. For this reason, all avenues which will made to bring together the principles of movie speed up the learning process should be ex- projection. Included are subsections on film for- plored thoroughly. Hopefully, the efforts stimu- mats, on projectors and their characteristics, on lated by new developments in audio-visual hard- lenses, sound, screens, and on some new devel- ware will be a start in this exploration. opments in still-projection techniques. This sec- Members of the writing team had an oppor- tion should serve as a handy guide when pur- tunity to visit an elementary school where com- chasing equipment and when setting it up so as to puters were used in an experimental project to obtain the best results. teach reading to first grade students and arith- Computer-assisted instruction. Chemists are metic to fourth grade students. The staff had just' starting to experiment with this new tool. not evaluated the effectiveness of the project but Hence, the experience here is sparse, and the they stated that although the youngsters seemed treatment is elementary. Diagrams are given to enjoy working briefly with the computer they illustrating the principal of shared time com- would do anything possible to get personal atten- puter use in instruction. A sample of student- tion. If this understandably human trait carries computer dialogue is included to indicate the over into the college age group, it suggests that kind of interaction that is possible here. While the best learning experience will continue to be thissampleincludesespeciallyelementary centered around a live teacher, but assisted by chemistry to make the point in limited space, the best that technology and a film maker's art actual computer lessons could be on topics con- can provide.

3 ,0, .'-*

TV close-up of anemerging infraredspectrum PORTABLE VIDEO TAPERECORDING SYSTEMS TV IN CHEMISTRY INSTRUCTION television and tape in the classroom continue to Television has been used in collegechemistry be used. courses in numerous ways, most often in general New Capabilities and New usesPerhaps the chemistry.' For example, chemistrydepartments greatest potential for television in increasing the in several schools including the University of quality of chemistry instruction lies in the utili- Minnesota and Purdue Universityhave used it zation of the recently developed, relatively infor pre-laboratory discussions andto illustrate expensive and rugged portable television tape specific laboratory techniques.At the University recorders. These recorders make it possible for of Texas and at Oregon StateUniversity the lec- even small chemistry departments to own a ture and laboratory portions of general chemistry closed-circuit television systema camera, a TV courses have been put on kinescopefilm. tape recorder and monitors or a projector. With The kinescopes have been usedrepeatedly at this equipment instructorscan utilize live TV the originating institution and they have been in their classrooms or theycan make their own telecast to neighboring colleges.At the Univer- tapes with a minimum of effort. sity of Florida general chemistry lectureswere taped and shown tomany small groups of stu- Video tape can record anything thatcan be dents thus eliminatingsome of the large sec- seen. It can do so simply and economically on tions. At Montana State University andat Rens- magnetic tape that can be erased forre-use selaer Polytechnic Institute live and tapedTV when the recorded information isno longer use- have been usedas a lecture demonstration aid. ful. Portable recorders, only twice thesize of a standard office typewriter,are priced from one Various techniques were used by the instruc- to four thousand dollars and can be used easily tors responsible for developing these television and dependably in the laboratoryor classroom by presentations. For example, at Oregon State instructorsorstudent-assistants.Immediate kinescopes of the lectures and laboratoryex- playback on any number of televisionscreens is periments were prepared and thesewere pro- as simple as the playback of audio tape. jected on largescreens. At most schools the taped or live presentationswere shown to stu- Video tape can bring into the classroom,in- dents on TV monitors located in classroomsor struments and apparatus that students would in laboratories. Classrooms of allsizes suitable never see otherwise. For example, the operation for groups of from 20 to 500 studentshave been of the mass spectrometer, and the details ofthe elector microscope equipped with monitors and usedsuccessfully or the sample chamber of a for TV presentations. spectrophotometer now can become availableto all students. Tapescan be prepared so that stu- A television camera locatedon the lecture dents can take readings from the dials table and used to magnify demonstrations, or from the to charts of the instruments being usedin the ex- transmit and enlarge a photograph or diagram, periment. In addition, uniqueor hard to arrange or to convey the instructor's written words have events can be recorded for repeated viewing. been used at Rensselaer and at Montana State. Video tape recording also stores andrepeats ma- In general, attempts to replace the live lec- terial of temporary interest whetherit be in- turer by an instructor appearing on a television structions to the multiple sections ofa teaching monitor have not persisted; however several of laboratory or a record ofa new teaching assis- the other applications, suchas the teaching of tant's conduct ofa class which he can later view laboratory techniques, magnification oflecture and criticize. experiments and demonstrations using both live The video tape recorderserves well as an

*We are grateful to the following for supplyingsummaries of their experiences with television teaching University of Florida; Professor R. C. Brasted, University of for this report: Professor J. F. Baxter, Minnesota; Professor R. L. Livingston, PurdueUniversity; Professor L. 0. Morgan, University of Texas; Professor R. O'Connor, Kent StateUniversity (experience at Montana State); Professor Institute; Professor W. H. Slabaugh, Oregon State University. H. Richtol, Rensselaer Polytechnic

5 IIMMIIIIM111/

erasable slate on which to try, test andimmedi- pare tapes ofexperiments, demonstrations, mod- ately criticizevisual aidsto understanding els, or other instructionalfeatures which they chemical principles and practices. It is a me- felt could be shown moreeffectively by this dium for impromptu creativity. Onthe spur of medium than by conventional methodsof pre- the moment, an instructor can record anillus- sentation. Without exception,all of these teach- tration for his lecture. After usingit, he can ers wereimpressed with the potential of this decide whether the recording shouldbe saved, medium and with the ruggedness and easeof altered or erased and forgotten. Ingeneral, operation of the equipment.Table TV-1 is a video tape recording should be usedwhen it summary of thekinds of tapes prepared in this can providelearning situations not available project. of other otherwise. In addition to these tapes, a variety During the summer of 1966,television tape applications made possible by chemistrydepart- recorders and cameras were sent tochemists at ment-owned-and-operated video systems have several colleges and universities. Theseteachers been tried or suggested. Some of these arelisted were asked to testthe equipment and to pre- in Tables TV-2 and TV-3.

TABLE TV-1

Examples of Tapes Prepared by ChemistsUsing Portable Video Recorders . A.1... Description of Tape Prepared Topic .

...... p.ii, spectrophoto- Spectrophotometer Preparation of sample; loading and operating meter; interior operation ofinstrument.

MR Spectromater. Preparation of sample; loadingfii-idoperation of instrument Preparation of sample; loading x-raycamara;:*iii ur X-ray Power Analysis , . line separations. ,

McLeod Gauge Operation and reading of instrument. Preparation of sample; operation and readingof instrume Vapor- Liquid, Chromatography

Recorded directly; camera mounted on tnit , 0 f.i. Crystallization .;,..,..f% Reading Burets Meniscus spread across TV screen. - ,...z across IV ing Charts Charts and oscilloscope screen spread reading can be made from monitor.

,., In' Ion of valcuMW, .. ,, , - .

TABLE TV-2

Ses of TV Tapes inChemistry Laboratory Instruction e, taborilbsy Examinations

Crystallization plete experiments

rxrid post-lab sessiOns 4:01.1`Meters itration nirparies Octets from g roPhotorn ,Quantitative transfer A

vy /\ /

=1111=1.

TABLE TV-3

In preparing such a tapesequence, the instructor ordinarily would arrange the materials and then rehearse what he plansto do with the camera turned on and with the output made directly into the monitor. In thisway, he or the assistant can see each operationas it will eventually appear on tape. Even after rehearsalsand recording on the tape, ifa particular sequence is unsatisfactory, it isvery simple to erase the tape and re-record the section. All of these capabilities needto be explored and exploited in college chemistry. To doso requires some familiarity with the underlying principles, nomenclature and equipment oftele- vision tape recording. Following isa brief discussion of the equipment needed for videorecording includingsources and costs. This will be followed bya brief discussion of some principles of video tape recording. Close-up of a buret as seen on a video monitor Preparation of Video TapesIn many educa- CLOSED CIRCUIT TELEVISION SYSTEMS tional situations it is desirableto present pic- The essential components neededin a basic torially a concept, techniqueor process in an system for live video recordingare indicated informal manner. For instance,a brief illustra- in Figure TV-I. Although the first portable video tion of an extraction with a separatory funnel tape recorders required an engineer in attend- compared to the operation ofa counter-current ance, now any of the professional ornear pro- distribution apparatus could easily be recorded fessional staff associated witha chemistry de- in the afternoon or evening fora presentation partment can learn to operateone in a few the next day. Such taping could be done by the minutes. Probably the biggest change in the last faculty member with the assistance ofa teach- year, however, is the advent of really goodre- Mg assistant. In general, while the facultymem- corders priced under $5000. Examples ofthese ber needs to haveaccess to the expertise of an and slightly more expensive recordersare given audio-visual man or department, the production in Table TV-4. Witha camera and all necessary of a video tape should be and easilycan be accessories, the total price fora modest but thor- under the sole direction of the subjectexpert, oughly useful beginning televisionrecording the faculty member. installation is under $7500.

7 E.*

An AMPEX video tape recorder FIGURE TV-1 Elements of a video recording system TABLE TV-4

Representative Portable Television TapeReawders

Ampex Sony Ampex Sony Concord Whom* WO PV120 7000 tv-200 VIR400 150 1.. SP .i PO ,Tape Size 2" 2" 1" Max. Playing 1' . Time/1 reel 4 hr. 90 min. 1 hr. 1 hr. Tape. , :Sound Capabil- I Ch au; tpien. , ity, (Channels.) 2 1 Churr Char I C , `Remote Controls , , 'Useful for corn. Cleteete remote No

operation. , !Tose of Opera- Von: Rapid Fd'wd. Yes Yes No Yes No Yes Yes Yes `» Rapid Reverse. Yes Yes Yes Yes Fair Fair ,Stop Motion. Fair Good Fair Good No Allow Motion No Good No Good No Video w Video Output Video Video Video Vide' R.F., R.F. , R.F. esolution* l Not center lines, 320 350 320 250 Available r. orizontal)

Pe SPeed. 7.5 7.6 Inches/sec. 3.7 4.5 9.6 7.8 12 ,'eight 00 lb. 150 lb. 100 lb. 88 lb. 52 lb. 45 lb. 50 lb. Cost of 1 $59,50 $39.95 $39.95 r. tape $70.00 $75.00 x$59.50 $69.00 $149 Recorder Price $8000. $8950. $3150. $4200. $1150. $1250. from camera to monitor. Resolution of the *Picture quality is affected by signal-tnoise ratiosand other factors in the chain of equipment television picture. recorder should not be taken as the sole factor fordetermining good definition in the reproduced

8 The basic video recording installation.The fol- erate compromise in quality is necessary for lowing basiccomponents are needed in any reasons of economy, the Setchell-Carlson model initial installation: 2100 would be a good choice. Television projec- One camera with internal 2:1 synchro- tors which project the video image on large nizing generator suchas General screens are available and have been successfully Electric TE-20A $1595.00 demonstrated. Table TV-5 lists some TV monitors and projectors, their characteristics and One zoom lens such as Angenieux 25- costs. 100 mm f 2.8 with close-up attachment and extension tubes 450.00 As a practical consideration, it is important to use unmodified industry-standard components One tripod, head and dolly suchas and connectors in assembling the basic installa- Quick-Set Samson tripod(7301), tion to permit ready introduction of additional head (7201) and dolly (7601) .... 148.00 equipment. One camera monitor-receiver suchas the 5-inch Sony PVJ-305 RU 260.00 Expansion of the basic video recording installa- tionThe first component likely to be added to One omni-directional dynamic micro the basic video system is a second camera to per- phone such as Sony F-91 90.00 mit rapid switches from close-ups to wide-angle One one-inch video tape recorder with views. Table TV-6 gives some representative TV slow and stop motion capability such cameras, their characteristics and costs. In addi- as Sony EV-200 4200.00 tion to the cost of the camera, some switching One 23-inch viewing monitor such as system and a slight alteration in the camera sync Conrac model CVA23 400.00 system is necessary. The swi cching system may Total$7143.00 be a simple switch costing less than $75.00 ( Pack- ard-Bell VS -3) or a dissolving device which pro- Where the full horizontal resolution capabili- vides the capability of a continuous blend from ties of the camera are to be reproduced and one camera to another. The General Electric maximum reliability is required, a Conrac in- TC-59A switcher-fader costing $700 will do an dustrial type monitor should be used. If a mod- adequate job for simple systems. )

TABLE TV-5

Representative Television Monitors and Projectors

MONITORS Sotcliall Carlson Modr1 2100

9 TABLE TV-6

4'0

'!ft:1,,"

When two cameras are available, it is also length lenses are generally sharper than zoom possible to use a special effects generator such lenses. A turret with several fixed focal length as Ball Brothers Mark VI-A ( about $1,375 plus lenses costs as much as a first class zoom lens $50 camera modification ). Video information although not affording the zoom capability. such as captions or numerical data can be super- Angenieux zoom lenses are considered to be of imposed by means of the special effects genera- excellentquality.Regardlessof the lenses tor over the primary video image ("matting"), chosen, a set of standard C mount lens exten- or such information as close-ups of instrument sion tubes ( $19.50) is handy for close-up work parts and diagrams can be inserted onto a se- in the laboratory and any supplementary close- lected portion of the screen ( split screen tech- up attachments supplied by the manufacturer nique). for a particular lens are generally worthwhile accessories. Additional lenses for the camera may event- While TV cameras will accept any standard ually be desired. If funds are available, the basic 16 mm C Mount lens, many of these lenses are camera might well be equipped initially with a designed for photographic cameras and are 10:1 rather than a 4:1 zoom lens such as the not suitable for television cameras. Lenses with Angenieux 15-150 mm f 2.8 for $790. A turret a maximum opening of f/1.9 or f/1.4 and having carrying a zoom lens and a one-inch fixed focal working distance no longer than 24" and as short length lens for high definition close-up work is as 18" probably will be most useful for the work a logical step beyond a single lens. Fixed focal described here.

10 Abasic camera can be equippedas follows: common. A distribution amplifier is needed only Turret mount when very long cables are required ( as fromone Three lens turret, $196.50 building to another) or when parallel rather than Lens, 1" f/1.5 85.00 series connections are required in a branching distribution to different rooms or buildings. Lens, 2" f/1.8 122.00 If many outlets are neededover a large area, Lens, 6" f/2.8 119.00 it is possible that conversion toan RF signal Extension tubes for extreme close-up might be justified. In the lattercase, several in- work 20.00 dependent signals can be transmittedover the same coaxial cables, or transmission can be $542.50 broadcast over the 2500 megacycle channel al- Turret mount located to educational institutions. Nevertheless, Three lens turret, $196.50 it is significant that experienced televisionusers Lens, 1" f/1.5 85.00 consider high resolution to be the most import- Lens, Zoom f/2.8 ant quality required for scientific purposes. The RF 4-1 (17 mm-70 mm) 400.00 best system will not transmit pictures as sharp as a video-audio cable system. Extension tubes 20.00 LightingUsable video picturescan be made $701.50 with standard equipment in light levelstoo low Single lens mount for comfortable reading. Consequently, existing Lens, Zoom f/2.8 room light often is perfectly satisfactory. If addi- 10-1 (15 mm-150 mm) $790.00 tional lighting is required, simple lamps ordin- Close-up rings 40.00 arily are sufficient. Chemists should know that high intensity lightsuch as burning magnesium $830.00 can destroy a vidicon camera tube. Camera supports..A number of excellentcam- MaintenanceTelevision recorderheads re- era supports are available from "Quick-Set", quire regular maintenance not unlike thatre- Inc., Skokie, Illinois. In addition to the tripods quired for instruments used constantly by chem- and pan head recommended in the "starter set", ists. The SONY and AMPEX recorders used in an elevating camera support is available which these studies are remarkably rugged and require can be built into the lecture demonstration little service as new instruments. This equipment bench. This type of supportcan be used in two has been shipped around the country by plane, ways: One, to insure that the instructor will rail, bus and car. It rarely has failedto operate. have a convenient solid supporton the lecture However, the recorders are largely transistorized bench if he wants to use a livecamera in class; and complex. Moreover, their recording and and, two, on a cart designed to hold the TVtape video heads have lifetimes of 500 hoursor more recorder, camera and monitor. The cart and its and must be changed periodically. For these contents is a complete closed circuit TV system reasons, recorders must be repaired by especi- and can be wheeled into laboratories to make ally trained technicians.Manufacturers will recordings or into classroomsor teaching labora- train appropriate personnel to maintain andre- tories to display a taped or live video sequence. pair their equipment. Regional service facilities Distribution of television signalsUse of more are available for SONY and AMPEX. Many than one viewing screen requires knowledge of dealers offer service contracts. the best method of connection. Whenever the Video Tape The life of a video tape is limited. recorder video output can be sent fromone Depending on the manufacturer of thetape, monitor to another in one continuous chain, it and recorder, it has been estimated that from is only necessary to tie them together in series 100-1000 "passes"can be expected during nor- fashion with a cable for video andone for audio. mal tape usage. A pass is definedas any time the Installations with as many as ten monitorsare video tape goes past the recorder heads,e. g.,to

11 111101,

record and play back one scene wouldinvolve video tape recorders, and a lecturebench cam- two passes of the tape. Fastforward and re-wind era in thegeneral chemistry lectures. modes are not considered a pass, asthe tape Color Television Although color television tension is released and the tape isthus not in would be desirable, and in some cases necessary pressure with therecorder heads. In common to the chemistconsidering the use of this me- color TV will usage, the term playand pass are considered to dium, it will be some time before require- be equivalent. be suitable for chemistry's exacting ments. At present, colortelevision cameras sell for $60,000 to $70,000, and colorvideo monitors are priced from$2,500 up. In addition, the picture resolution islower than that of a comparable monochrome picture. Colorstandards also are hard tomaintain over existing distribution systems. Chlorine gas, forexample, can easily be green, blue, orshades between, depending upon -""111111, how the receiver is adjusted. Industrial sources indicate that it maybe at least three years before a significantchange is made in color television cameras and monitors. Even with major changes promised,the price of A SONY video tape recorder color equipment possible will be noless than Large Screen Television ProjectionThe design one-half the cost of color today. of many chemistry classrooms is not convenient Color television using an unconventional prin- for the placement of TV viewing monitors.If ciple has been demonstrated by Japanese manu- with the students are expected to takedata from the facturers. However, it is not compatible television picture, optimum locations foreach Americanstandards.Althoughconsiderably in viewer should be considered. lower in price, its potential and availability 1967. In general, students should sit nofurther than this country will not be known until late 20 feet from a 23" TV monitor.Excellent recom- Manufacturers of most portable recorders are mendations for monitor placement areavailable prepared to add color capability by next year. in Design for EducationalTV by Educational The cost for adding this feature according to one Facilities Laboratory, New York, N. Y.,1960. manufacturer will be close to the presentsell- By contrast, one large-screenTV projector can ing price of the one inch recorder. accommodate the entire class with asimplified installation. Projectors are availablewhich project a TV image up to 20feet wide ( see discussion of optimum image sizein film section) . Most currently availableTV projectors are limited in that their light output is solow that a semi-dark or acompletely dark classroom is necessary. Alsothe lenses available on many models require the projector to beplaced in a close relationship to the screen.This could be troublesome in the traditionallydesigned chemistry auditorium. The costfor the larger TV projectors is quite high. Aninstallation of a large screen TV projectoris now being made in a 350 seat capacity chemistryauditorium at Ohio Front view of a TV camera showing several lensesmounted State University. Plans are to usethe projector, on a turret.

12 PRINCIPLES OF VIDEOTAPE RECORDING Role of television cameras and accessoriesThe first step in a television system is to generatean first field second field electrical equivalent of thescene. By means of a lens the subject is brought into focus on a MM. photoconductive surface in the pickup tube of 011111 =1 MEM the camera and the resulting image is scanned by an electron beam. The amount of light the OM OM IMO MIN .11=1 4110 beam encounters at any instant determines the - --:'="110 magnitude of the camera tube current and hence Mt 4110 ONE. MEM 41116 111. the video signal from the camera. Sinc.?, the .11.1ND OM OM .11.1ND video signal ultimately modulates the intensity of an electron beam which scans across the face of the television viewing screen, it is necessary that the camera tube and viewing screen scan- FIGURE TV-2 ning be synchronized. A synchronizing genera- Interlaced scanning principal tor built into the camera or elsewhere in the system generates electrical pulses which lock to- placed horizontally half a line. The ecmplete gether the scanning beams in the camera and frame therefore contains 525 scanning lines. monitor. Scanning speed is such as to generate the television picture at the rate of thirty frames a The light sensitive tube used in cameras under second. consideration here is called a vidicon tube. It Video tape recordingVideo tape recording is ishighly sensitive, sturdy, and costs abot t presently accomplished by methods quite simi- 3 $170.00. Image-orthicon tubes used incommer- lar to magnetic sound recording. The essential cial television are expensive, bulky and delicate. parts of a video recorder (Figure TV -3) are a They need not be considered for the applica- magnetic tape, some kind of tape transport tions discussed here. mechanism, and the recording (or playback ) The electron beam of a vidicon tube sweeps across the light sensitive surface from left to right so as to divide the image into 525 horizontal segments called lines. Each line segment of 1101 the video signal is ultimately reassembled in the camera camera monitor where the scanning beam starts at the signal top left of the image and sweeps to the right and down at a uniform rate (figure TV-2). At the end of each sweep line, the beam returns (/) rapidly to the beginning of the next line in its tape field. During this retrace period, no video signal transport magnetic magnetic exists. tape head

An interlaced scanning system is used to re- 11.1.1111. duce flicker. The scanning beam skips every FIGURE TV-3 other line down the screen, then returns to the Elements of a video tape recorder top to scan the alternate lines interlaced be- head. The recording head converts the modu- tween the first set. Each set of horizontal lines lated electrical signal from the camera into a is called a field, and the two combined sets are variable magnetic field which impresses a pat- called a frame. Since each field contains 262I/2 tern of magnetization into the magnetically lines, the beginning of the second field is dis- susceptible coating on the recording tape.

13 Playback of the recorded signal is accomplished by passing themagnetized tape across the head. As the head moves pastthe tape, the varying magnetic field generates amodulated output voltage whichcontrols the electron beam scanning the monitor screen. Video recorder heads A videorecording head, like that of an audio recorder,consists of a magnetic element interruptedby a nonmagnetic gap across whichthe tape passes. The widthof this head gap is importantbecause it is related directly to the upper limit ofrecordable signal FIGURE TV-5 frequency: Diagram of a video tape recorder with a partialhelical-wrap rotating head tape speed maximum recordable signal frequency head gap The tape travels past the recordinghead at a Heads can be manufactured torecord high fidel- relative slow speed while the recordinghead ity sound ( 20,000cycles per second) at tape revolves rapidly( 1800 - 3600 r.p.m. ) in the op- speeds of 71/2 inches persecond or less using posite direction. This system ("slant track re- head gaps of the order offive microns, but good cording") places the video signal on the tape as a video recording requires responsein excess of series of diagonal lines ( FigureTV-6) at a "writ- four megacycles. Fixedhead video recorders ing" speed of perhaps 680 inches or moreof tape operate very much asdo their audio counter- surface per second. parts and in principle representthe simplest and therefore the most inexpensiverecorder mechanism. Nevertheless,they require either exceedingly high tape transport speeds or anextraordinarily narrow head gap.Although prototype fixedhead machines have beendemonstrated, no manufacturer presentlymarkets one. Attention is now focused on the developmentof ingenious rotating heads whichprovide high effective tape speeds at an economical rateof tape transport. Rotating video recorderheadsPortable recorders utilize tapewound around a rotating head in a helix ( FigureTV-4 ); FIGURE TV-6 or a segmentof a helix ( Figure TV-5 ) Illustrating a slant track video tape recording Although helical scan recorders generallydo not meet the standardsof studio machines in broadcast television, they are entirelyadequate for all but the most critical highresolution educational applications and at the same timeoffer simplicity, dependability, andportability at a low price. Helical scan recorders usingmagnetic tape either one or twoinches wide can give pictures sufficiently sharpfor scientific uses. Image sharpness in video recordingsThe most significant figure used to describe the meritof FIGURE 'TV-4 a television system isits horizontal resolution Full helical-wrap rotating headfor video recorder

14 ..MmaramMIM i.e. the number of vertical lines thancan be dif- corders. These tapes contain stair-step, Multi- ferentiated in the width of the picture. ( Lines burst and Windowed-sine squared test patterns resolved by a system should not be confused and are designed tostandardize resolution with the number of lines scanned by thecamera measurements and to aid in instrument adjust- or monitor.) The best commercial broadcast ment. Copies of these tapes are available. Their television systems resolve 350 lines, but 300 use should help make possible the exchange of line resolution on a home receiver is considered tapes from one school to another with a mini- excellent. One-inch tape recorders of the type mum loss in picture quality. considered should resolveover 300 lines and a SELECTED REFERENCES half-inch tape recorder should approach 200 line 1. Closed Circuit Television-Definitions: Electronics resolution. Industries Association, 11 West 42nd Street, Image sharpness on the monitor screen is a New York 36, New York ($1.00) subjective quality that depends not aloneon line One hundred and thirty definitions, formulated resolution. Lighting and subject contrast also by EIA Engineering Committee on Closed Circuit affect sharpness. Inexperienced video photog- Television are listed. Ranging from "Aspect raphers can profitably study techniques used by Ratio" to "white compression," the definitions film photographers. Since the imageon a view- cover terms one will encounter in using video ing screen is influenced by the quality of each equipment. component in the total system, equipment of 2. Fundamentals of Television and Essential Optics comparable quality throughout is recommended. (EBI-3711), General Electric, Electronics Park, Syracuse, New York, 1964. (8 pages, free) It would seem unwise for example to usea cam- 3. Fundamentals of The Vidicon Tube and Transis- era capable of resolving 800 lines with a tape tor Characteristics (EBI.3781A) General Elec- reporder capable of only 200 lines of resolution. tric, Electronics Park, Syracuse, New York, 1964 Editing, Interchangeability andStandardsUn- (7 pages, free) needed footage can be edited from video tape 4. Enger, Richard A. (ed.) Teaching with Videotape. by two methods. The first involves recording St. Paul, Minnesota: Dept. of Communication, the information from one tape to another, 3M Company, 1961 (free) omitting the unneeded portions in the transfer. The value of this publication is limited by the The edited copy will contain very short periods developments in video tape recorders since of "snow" ( noise) indicating the stopping of the 1961. recorder at the editing points. The second 5. Lewis,Philip.EducationalTelevision Guide method of editing involves physically cutting Book. New York: McGraw-Hill, 1961. ($5.50) and splicing the tape. Inexpensive tape splicing A textbook for the serious student of educational television. Closed circuit television is treated blocks can be made in the machine shop. Splic- in detail. ing instructions are supplied with the recorders. 6. Schaefer, Chris H. and Suzman, Cedric L. Video "Electronics Editors" are supplied withexpen- Tape Recording, Hobbs, Dorman & Co. Inc. New sive recorders. York, 1965 ($12.00) While tapes usually can be transferred from A comprehensive and carefully documentedre- one tape recorder to another of the same manu- port on "Video tape recording" with latest facturer without significant loss of picture qual- information on video tape technology and record- ity, it is not possible to interchange tapes being equipment. An instructive book for thecom- tween recorders made by different manufac- munications industry, the businessman, and the turers. This is because the design of the video general public. A comprehensive bibliography is included. recorder heads varies considerably amongman- 7. Wade, Warren L. Television Tape Recording Sys- ufacturers. tems: A Guide for School Administrators, Janu- Since few standards are available to assure ary, 1964. Reprinted by Ampex Corporation, consistent reproducibility of tapes made on Redwood City, California (free) helical-scan recorders, the AC, has prepared An examination of portable television tapere- standard tapes for the AMPEX and SONYre- corders as they relate to school district needs.

15 t

I 11 ab

FILMS ANDFILM LOOPS

NEW USES FOR FILMS aged either to supply their own sound track or The mechanical and logistical problems asso- to turn off the sound on a motion picture and ciated with integregation of films as part of a talk. While it may be difficult when using lecture often have been a deterrent to their use. a long film to synchronizeone's own comments Obtaining a projector ( and often a projection- with what is going on in the film, the instantane- ist ), threading it, insuring that it is operating ous stopping mechanism on the newer projectors properly, and that the film will be successfully enables the teacher to hold on one frame, to dis- run without a breakdown, are conditions not cuss a pointappropriately, and to resume the easily met. Too often the classroom showing be- motion when ready. The versatility of modern comes a parody on the debacle commonly projectors is encouraging the production of sin- called home movies. Nor does the solution of gle-concept films in which synchronization be- the mechanical problems end the difficulties. tween the sound and the picture is much less The majority of films which have been available critical than in traditional teaching movies. on chemical subjects were not designedfor A growing number of films particularly de- classroom use, and certainly not for classroom signed for college classroom work and for the use in the light of the subject matter as it is level of work which currently is being explored being presented today. at the college and university level, is becoming Considerable evidence is accumulating which available. Whereas in the past there were essen- suggests that if the mechanical problems can be tially no films potentially acceptable beyond the solved, and if the instructor can be continuously freshman level, it appears very likely that there informed of the sources and availability of good soon will be films which canbe used at any level, films, he will indeed use them in his classroom, including graduate courses. As chemistry be- 0 or in other segments of his course. comes more abstract, asinstruments become In recent years, the film industry with the more complex and more important, as itbecomes help of educational research groups has made essential to expose the student to a wider and unprecedented progress in minimizing mechani- wider range of ideas and equipment which can- caland logistical problems. Projectors are al- not easily be brought into the classroom,films ready on the commercial market which accept will become more and more important. Already cartridges containing film ready to project. films are being prepared in which the student Cartridge-loading projectors for short films ( of can see experimental databeing obtained and the order of four minutes) or for films ( of the can collect fromthe screen information which order of half an hour) are available. The projec- he can then work up and from which conclusions tors are quite small, reasonably priced, and can can be drawn. be left in the classroom, laboratory, or study As indicated earlier, motion pictures also are carrel most of the time. The cartridge merely is inserted into the machine, the film is shown and being used: a) to present specific chemical prob- then is immediately ready for projection again. lems to which student viewers may proceed to Even projectors for very large classrooms now seek solutions; b) in the laboratory to illustrate come equipped with automaticfilm threading specific techniques or to provide visual instruc- and rewind attachments. By means of remote tions for operating or for understanding the Controls located at the lecture table, these pro- principles associated with the operation of an jectors can be turned on or off, restarted, re- instrument; c) in study carrels equipped with versed, or so controlled that a single frame of cartridge-loading projectors by means of which a student may privately view afilm as many film can be held on the screen. Most films nowadays come with sound. Some times as he wishes. have provisions for addition of a second sound This section has been prepared to assist teach- track by the user. Instructors should be encour- ers who wish to learn moreabout these new VW*

.00

The reaction of potassium with chlorine photographed ,fron; CHEM Study color film "Chemical Families." directions in the utilization of filmsin college stop-action, time-lapse. Examples of the former chemistry instruction. It includes: follow. Some specific examples ofnew uses of films Single concept films.These are short, usu- and film techniquesas they apply to college ally four to ten minutes, filmson a single topic chemistry. such as vaporpressure, enthalpy, hexagonal and A list of sources of films, film loops andre- cubic closest packing, pH, the discoveryof views of films. oxygen-18, etc. Single concept filmsmay be used A summary of the equipment currently avail- as part of a classroom presentation or theymay able includingsources, approximate prices and be assigned for independent study.Students the background information neededto help may borrow, from the instructor or from the make an intelligent selection andwise use of library, cartridges containing assignedfilms and hardware. view the films from projectors locatedin study Some specific examples.Films might be classi- carrels. Alternatively, the projectors withcart- fied conveniently interms of their intended use ridges inserted and ready foruse might be lo- in teaching( pedagogical techniques ),or in cated in halls of the buildings,in laboratories, or terms of the special visual effects they illustrate in small classrooms. Some singleconcept films ( film techniques ). The latterare familiar from now available or in preparation are listed in commercial movies; examples include close-ups, Table F-1.

TABLEF-1

Some Single Concept Films Availableor In Preps, Tide Producer and characteristics Availability Infrared Spectra and Siabaugh-Ouellette; 4 minutes February 1967 Molecular Structure echnicolor cartridge Interpretation of Slabaugh-Barrow; 2 four minute February96 Vibration Spectra !pops, Technicolor cartridge An Electrochemical Cell efampbell-CHEMS, 4 minutes FobruorY 196/ (Animated Mechanism) Technicolor cartridge A Silver-Hydrogen Campbell-CHEMS; 4 minutes, AC3, February 1967 Electrochemical Cell Technicolor cartridge Molecular VibrationS tampbell-CHEMS; 4 minutes, February 1967r using Models `Technicolor cartridge

Atomic and Bonding Slebaugh- Parsons, 4 minutes, AC3, February 1967 Orbitals Technicolor cartridge Crystal Structure Slabaugh; 4 minutes, AC3, February 196 of Metals Technicolor cartridge

Filmed lecture experiments.Chemists em- cost, safety, size, geographical location, sensi- phasizing experimental methodsin their class- tivity of the instrument, conflict inuse, or time room teaching may have found that the class- required for preparation of theexperiment. Pos- room is too large for all students to adequately sibly the time factor in the performance ofthe view what is taking place in the experimenton experiment is either greater than the time which the lecture table. They alsomay have found that could be devoted to the experimentin the class- the equipmentnecessary to carry out the experi- room or too short for effective observation by ment appropriate to the class discussionwas in- the students. Under thesecircumstances filmed accessible to the lectureroom for reasons of experiments might be most appropriate.

19 .1110=1.

film might be pre- cussion of experimentaltechniques utilized Lecture experiments on of the possible pared locally or purchased.They might be in the experiment and experimental error and the in- utilized: source of fluences of such errors on theexperimental 1. To serve as the focal pointfor a dialogue results. between the teacher and thestudents, or 2. To serve as the methodof enabling the stu- among the students,preferably in the class- dent to make the observationsand to take room, concerningthe meaning or inter- data from the instruments used sothat he pretation of the experiment.Such dialogues may then analyzeand interpret the experi- generally involve the analysis ofthe data ment himself even thoughhe did not actu- or observations.They also may involve dis- ally perform it. TABLE F-2

Some Lecture Experiment Films Available orIn Preparation Avelibili(y ...... --.This Producer and Characteristics AC., february 1967 Potentiometric ,Slabaugh; 4 minutes, Titrations Technicolor cartridge Ionization Energies Distribution of Molecular Speeds Fall 1967 Electronic Spectra of 160 and 160 1967 Fall 1967 Mass Spectrometric Determination = of Mass and Relative Abundances of Isotopes of an Element

Utilization in the laboratory.Whereas films F-3. Instructors may now referstudents to utili- may be utilized inthe classroom to give every filmed examples of techniques, equipment student a "front row" seat, filmedand taped zation, or instrument operation as necessaryand material may be used in the laboratory:a) to appropriate to the student's work.Only those give every student individualizedinstruction students who are in need of thisparticular in- when and where it will be most appropriateto struction or information needbe required to his laboratory experience; b) tobetter organize spend their time viewing the film. laboratory instruction; and c) as themedia for In general, filmed and taped materials may labora- improved laboratory examinations.Mechanical be effectively employed to complement problems associated with such usesof films in tory teaching in four ways: the laboratory have been surmountedby using 1. To illustrate and standardizelaboratory cartridge-loading 8 mm projectors, bothwith operations that is to assist in the "telling and without synchronized sound. Using a rear- and showing" function of the laboratory. color screen attachment onthe projector, the film may An important example here is that be viewed in natural light as is atelevision standards such as endpoints for indicators faithfully reproduced on film with screen. These projectors mayalso be purchased can be with earphones so that several units maybe em- some effort. Inaddition magnification and ployed in a small room without audiointerfer- frame-slowing techniques make portions of the equipment and intimate details of proc- ence. esses vividlyaccessible. Safe practices and Short films in which various laboratory opera- safety precautions also can be forcefully tions are shown in a step-by-stepfashion are impressed on students with striking pic- becoming available. Examples are given inTable tures.

20 2.To extend the scope of the laboratory work 4.To individualize instruction that is to pre- by presenting, to the student, additional sent the individual student with the in- experiments in which data and observa- formation he needs in the laboratory at tions are generated and for which the stu- the time it will be most beneficial to his dent makes the analysis and interpretation learning. by himself. In courses where students are rotated among 3. To move from verbalized quizzes and ex- experiments, films on laboratory techniques and aminations toward laboratory practical ex- operations can remove a large burden from the aminations without becoming involved instructor thereby enabling him to work closer with massive logistical problems of admin- with the students in examining the significance istration of the examination. of the laboratory work.

TABLE F-3

Some Laboratorynstruction Films Available orn Praparation Producer and Characteristics Availability

Titration Slabaugh; 4 minutes February 1967 Technicolor cartridge Basic Laboratory Barnard; 5 minutes rA011e June 1967 Techniques Fairchild cartridge Thin Layer rnard; 6 minutes Os, June 1967 Chromatography 'Irchild cartridge Technique_s of Yolurletric University of Wisconsin; U. ofWisconsin Analysis sound, 30 minutes, 1(eilevision Center 16 mm reel Using A Filter Yale University; 2 minutes Association Films Quantitative Transfer Yale University; 17 minutes, Association Films sound

TABLE F-4

Some Instrument Instruction Films

,Titts Producer andCharacteristics Availability

, Operation of the Slabaugh; 4 minutes, Ace February 1967 Mettler. Balance Technicolor cartridge

, Single Pan Sartorius Slabaugh; 4 minutes , 1 ary 1947 , Balance nicolor carttidge Operation of the Ouellette; 4 minute i'Apri11967 Beckman IR8 Spectrophotorneter Technicolor cartridge

,. 'Operation of the Fell1967 , , , B. and L. Spectronic 20 peration of the Vapor, II I

(A , ; Jr 4 . *

21 11=11111111/ hi

Instrument instruction films.These films show the student the details of construction and operation of an instrument, as well as someof the basic laboratory techniques and safety precautions pertinent to its successful use. In practice a cartridge-loading projector containingthe filmis placed beside the instrument inthe laboratory. A student views the film or portions of it any time he feels the need. With such films, the usual check-out period for an instrument ( e.g. UV, IR, nmr, Raman, etc. ) can be greatly abbreviated or eliminated. Examples of instrument instruction films nowavailable or in preparation are given in Table F-4. ( See page 21. ) Laboratory examinations via films and tapes. Films and tapes offer two significant break- throughs in laboratory examinations. First, they laboratory allow the instructor to move toward The reaction of xenon with platinum hexafluoride.Photo- examination. Secondly, they allow him toevalu- graphed from the color film "Xenon Tetrafluoride," pro- ate student learning andunderstanding of duced by Argonne National Laboratories. various parts of the experiment. Suchevaluation used to explain the solutions to theproblems may be usedeither for grading purposes or for and questions. This may also be done forsample approval to proceed to a situation of greater calcualtions from experiments. complexity. Another technique is to put the lectures on Items which have been used or suggestedfor audio-tape or on film with sound. In such in- filmed or taped laboratory examinations include: stances, students absent fromlecture and those 1) the prediction of the effects ofchanging wishing to clarify their understanding ofclass various experimental parameters; 2) thedesign material may do so. Such out-of-class viewing of an experiment to test a hypothesis; 3)the programs have beenoperated in one of two formulation of an hypothesis from the evidence ways: 1) space isprovided within the depart- presented; 4) the ordering of data; 5) thedesign ment for the projectionand listening devices; of experiments to achieve a specificobjective; 2) instructional materials are available through 6) the determination of knowledgeof experi- an audio-visual center.In such facilities a stu- mental tools; 7) specific observations;8) the dent may be able to dial and see any of a variety surveillance of errors in technique; and 9) the of films stored in the audio-visual center. identificationoflaboratoryoperationsand Coordinated use of different film and tape equipment. materials.Severalinstructionalexperiments In addition to films, slides and transparencies now areunderway which make available to the also have been used as mechanisms foradminis- instructor in his classroom or to the students in tering laboratory examinations. laboratory-study carrel combinations the capa- Films for non-scheduled time.Some instruc- bilities of several mediafilms, sound TV tape, tors assign a given film forout-of-class viewing overhead projector. prior to the consideration ofthe topic in the One of the most successful of these is the class, just as they would make anassignment in audio-tutorial laboratory developed by S. N. the textbook. The film treatmentof the subject Postlethwaite in the Botany Department at Pur- then serves as the basis for theclass discussion. due. In this laboratory, the student has at his In selected cases, solutions toproblem sets disposal in addition to the usual botany labora- and examinations are available onslides or film tory facilities, study carrels containingfilm pro- strips. Synchronized soundtechniques may be jectors and audio tape recorders. Each student

22 for this purpose. Each studentgauges his own progress with quizzes winch either send him forward to new materialsor back over some of the same material. A chemistryprogram similar to this is now in progress at Cornell. Many schools now have lecturerooms equipped with facilities for slide, film,TV and overhead projection. Instructorscan control any of these from the lecture tableor may use any combination in a given lecture. One technique frequently used in these classroomsis to display related informationon two screens simultaneously. The instructor then shows therelation- ships or draws comparisions between theinfor- mation appearing on the twoscreens. Ancillary materials for films andtapes. Because students often do not takenotes during a film or tape presentation, many instructors have found it especially helpful toprepare study guides or quizzes which studentsmay take with them. Making these materials available for studybe- fore viewing the film sometimes helpsa student become more alert to the importantconcepts presented and may An electron density map of molecular structure anda field encourage him to search for emission microscope picture of a platinum crystal.Photo- answers to questions as he views the film. graphed from the color film "Electronic Processesin Crys- tals" produced by Tokyo Cinema, Inc. Teachers preparing films for distributionare comes to laboratory when he wishes and while urged to supplyresource guides for these films. there proceeds at hisown pace. In this way potentialusers can know the pur- In the study carrel, the student listensto au- pose and content of a film and may gain infor- dio tapes specially prepared by theinstructor mation that will enable them touse it more for the unitor experiment under study. Instruc- effectively. tions on the audio tape may direct the studentto Filming techniques.Many of these techniques the laboratory benchor to view a film also pre- have been used effectively in chemistry filmsas pared especially for thisuse, or to a reading the examples in Table F-5 illustrate. Theseex- assignment. If a student needs help, hecan ap- amples shouldprove particularly useful to those proach an instructoron duty in the laboratory planning to make theirown teaching films. TABLEF-5

Ostel growth, iheinitiel Assolution, ,.41;rystal growth, cniital struCture;\ei ing of instruments ssottrOg a saallt,MOSOLliarY

23 Tr,

and for the List contains 92films produced by CHEMISTRY FILMS topics SOURCES OF Argonne NationalLaboratory covering been made to In the past noconcerted effort has ranging from thegeneral nature ofthe Ar- of existing prod acarefully-edited catalogue Laboratory to specificexperiments Hopefully such gonne chemistry films withuseful reviews. recorded for highlytrained experts. Films are during the next year. a cataloguewill be available available on loan at nocharge (other than return postage andinsurance). Listingincludes Film Directories number, date, time,sound, Edition) title, catalogue 1. Index ofChemistry Films (Fourth and color informationplus a paragraph sum- Chemistry Royal Institute of mary of thesubject content ofthe film. London W.C.1, Eng. 30 Russell Square, 5. Films onThe NuclearSciences (1966 cata- most comprehensivelisting This index is the logue of films onchemical topics currentlyavail- Film Library film- National Science able. Approximately1400 films and 400 Canadian Film Institute than 200 sources arein- strips from more 1762 CarlingAvenue produced cluded. The fourthedition lists films Ottawa, 13, Ontario,Canada by through September1964. Designed for use available from the and Summaries of 254 films are schools, technicalcolleges, universities Science Film Library.In- departments of industrialfirms, Canadian National the training formation is given oneach film including offerings from theUSA, this index includes production date,length, whether and 20 othercountries. It country and United Kingdom black and white orcolor, languageversions subject classificationsand technical or contains 127 film available, producerand sponsor, classifications and costsapproxi- and 77 film strip scientific adviser,description of content, mately $1.10prepaid. service charge orrental. The sections ongen- Chemicals, Chemistry,and the 2. Film Guide on eral theory andprinciples, chemistryand Chemical Industry,1965.66 Edition radiation andradioisotopes Association, Inc. metallurgy, and Manufacturing Chemists' contain details on manyfilms suitable for use Avenue N.W. 1825 Connecticut in colleges anduniversities. Washington, D. C.20009 Mines Films,1965-1966 311 films from100 sources 6. Bureau of List contains MOTION PICTURES of chemistry,chemicals covering many facets Bureau of Mines industry, andsuitable for and the chemical 4800 ForbesAve., Pittsburgh,Pa. 15213 college students. manyaudiences including information on 40films 16 Tabulation includes 3. UnitedStates AtomicEnergy Commission to thetechnological as- Level, 1965 with many relevant mm FilmCatalog, Professional pects of chemistry.These films areavailable charge ex- Audio-Visual Branch from the Bureauof Mines without Information Division of Public cept for returnpostage. Listincludes informa- U.S. AtomicEnergy Commission tion on film title,time, mailingweight, pro- Washington, D. C.20545 and a summaryof the film technical films are ducer of the film, 186 professional-level content. from ten domesticUSAEC film made abailable 7. SourceDirectory: EducationalSingle-Concept libraries on a freeloan basis foreducational, Magi-Cartridges (Thirdedi- List- Films Available in non-profit, andnon-commercial viewing. sound, color, tion, March 1966) ing includestitle, date, time, Commercial andEducational Division and loaninformation plus a producer, sale of the Technicolor Corporation comprehensiveparagraph summary Box 517, CostaMesa, California92627 "Understanding subject contentof the film. This is a currentlist of educationalfilm pro- Series", and the"1964 GenevaFilm the Atom ducers andrespective listingsof single-con- from this source. Series" are available cept filmsavailable inMagi-Cartridges for National LaboratoryCatalogue of 8mm and 4. Argonne useinTechnicolor Standard It includes Motion PictureFilms Super-8 InstantMovie Projectors. Film Center,Bldg. 2 66 titles onchemical topicsavailable from Laboratory Argonne National seven sources. 9700 So. CassAve., Argonne,Ill. 60440

24 ..1110,

Other Film Sources ing footage from existing films. These films Several series of films, film strips, andtrans- are available only for examination and stimu- parencies have been prepared forthe chemistry lation purposes at the present time. classroom and are not completely reportedin the directories just described. Most of these filmshave 2. United Nations Educational Scientific and been prepared for beginning chemistryclasses or Cultural Organization for the in-service education of secondaryschool Pilot Project for Chemistry Teaching in Asia teachers. Division of Science Teaching, UNESCO Place de Fontenoy, Paris 7e, France Motion Pictures with Sound Approximately 10 films, generally dealing 1. Modern Learning Aids withexperimental topics treatedinan Division of Modern Talking Picture Service, "open-ended" manner have been made. Inc. Some emphasize the continuous variation methods developed in the Chemical Bond 3 East 54th Street, New York, N. Y. 10022 Approach. This source offers 26 CHEM Study Chemistry Films (available in both 16mm and8mm 3. The Nuffield Foundation sound cartridge formats). In addition 11 films Science Teaching Project on chemistry laboratory techniques (available Mary Ward House in 16mm), and three films titled "TheChemi- Tavistock Place, London S.C. 1 calElements"(availablein16mm) are Thirty-eight films have been prepared to offered. supplement the new "0" level (secondary 2. Coronet Films school) chemistry course development by Coronet Building, Chicago 1, Illinois Nuffield; this list includes loops on labora- Coronet offers the University of Akron Chem- tory techniques, theoretical concepts based istry Laboratory Series (available in16mm on experimentalobservations,measure- ment, industrial form), consisting of twenty-seven filmsand processes and uses of chemicals. the Coronet Chemistry Films set (availablein 16mm form), a series of twenty-one classroom films. 4. Association Films, inc. 600 Madison Ave. 3. Encyclopedia Britannica Films, Inc. New York, N. Y. 10022 1150 Wilmette Avenue Sixty-three chemistry films produced at Wilmette, Illinois 60091 Yale University are available withseven The Chemistry on Film Series (availablein showing demonstrations on the preparation 16mm form) consisting of one hundred sixty of oxygen, six showing demonstrationsre- films is offered. lated to physical and chemical changes, and twenty-two on miscellaneous topics includ- 8mm Film Loops, Short Form, Silent ing laboratory techniques, basic principles, 1. Advisory Council on College Chemistry and structure. Teaching Aids Committee Film Project Chemistry Department, Stanford University 5. Genco Educational Films Stanford, California 1800 Foster Ave., Chicago, Illinois 60640 Approximately 10 films have been produced Five flms related to the detection and effects at Oregon State University by W. H. Slabaugh of nuclear radiation are offered. illustrating what a chemist with ideas anda minimum of equipment can do to produce 6. Encyclopedia Britannica Films, Inc. 8mm film loops designed foruse in the col- 425 North Michigan Avenue lege classroom. Approximately10-single Chicago, Illinois 60611 concept films have been made by J. A. Camp- Five films related to states of matter and bell by extracting relevant footage from properties of matter and eight describing CHEM Study films. Five single concept films laboratory techniques in chemistryare avail- have been made by S. A. Schrage by excerpt- able.

7.1..: - - ,,y,w_LA2NuagaiwagiUiliatr.11 1...... Mr & 4m.m.....

7. Sutherland EducationalFilms 201 N. Occidental Blvd. Los Angeles, California90026 Four films on some fundamentalchemical concepts are listed. 8. Gateway Educational FilmsLtd. 470.472 Green Lanes Palmers Green, London N. 13,England Three films on paper chromatography,thin- layer chromatography, andelectrophoresis are offered. 9. Ha las and BatchelorCartoon Films, Ltd. Lysbeth House 10A Soho Square London, W. 1, England Eight films on atomic andmolecular structure are scheduled to bereleased in 1966. 10. International VisualsAids Center 691 Chaussee de Mons Brussels 7, Belgium topics re- Apparatus used in the preparationof xenon tetrafluoride Sixteen films on technological with a photograph of theoscilloscope trace of the product lated to chemistry have beenmade. identification in the mass spectrometer.Photographed from the color film "XenonTetrafluoride" produced by Argonne Transparency Sets National Laboratories. AND USES 1. John Colburn Associates,Inc. EQUIPMENT: ITS AVAILABILITY P.O. Box 1236 Basic to the renewed interestin using film in 1122 Central Ave. the chemistry classroomand laboratory is the Wilmette, Illinois 60091 introduction by the industryofunproved film, offer a gen- Tecnifac Overhead Projecturals filmformats and complementinghardware. eral chemistry set offifty-nine projectuals With these new developments comesan in- (with overlays) and a 48 pageteacher's guide. creased need for the chemistryteacher to under- 2. Keuffel and EsserCompany of the new hard- Hoboken, New Jersey stand not only the capabilities the overhead pro- ware but also someof the important principles Spectra transparencies for this section is infor- jector for chemistry areoffered. This is a set of projection. Included in their of eighty transparencies(with overlays). mation on filmformats, projectors and 3. General Aniline andFilm Corporation characteristics, sound screensand some new de- 140 West 51st St. velopments in still projectiontechniques. The New York, New York10020 aim here is to provide ahandy guide for the pur- Projecto Aid Transparenciesconsisting of a chase and the setting upof equipment so that chemistry set of fivetransparancies are the best results can beobtained. offered. Film types.There are currently fourforms of 2 x 2 Inch ColorSlides 8mm motion picturefilms on the market in addi- 1. Geographical SlideService tion to the traditional16mmformat. These are 845 Outer Drive the regular 8mm, Super-8,Format M and a Jap- State College, Penna. 16801 aneseproduct. Of these theregular 8mm and Slides on minerals andmanufacturing sub- the Super-8 have beenused most extensively in jects are available. teaching films. 2. American Museumof Natural History The image area on the Super-8film is 52 per- Street Central Park West at 70th cent larger thanthat of the regular 8mm.Con- New York, N. Y. 10024 format offers a brighter rocks, and sequently the Super-8 Slides on snow crystals, common that obtained from a minerals are available. and sharper picture than

26 regular 8mm material under comparable condi- The running time of the 8mm films is approxi- tions. Both regular 8mm and Super-8can give mately twice that of the 16mm. For example at magnetic sound prints with a quality comparable silent speed ( 18 f.p.s. ) 100 feet of 16mm film to present 16mm optical sound. Because the will run in about 4 minutes while only 50 feet sprocket holesare smaller and further apart on of regular 8mm film will run in about the same Super-8 film than on regular 8mm film, each of time. the 8mm formats requires itsown projectors and cameras. However, several manufacturers offer Projectors.Table F-6 gives some examples of equipment which can be converted from regular film projectors, their important characteristics to Super-8 with minor adjustn-.?nts. and manufacturers.

TABLE F-6

Saw Front Screen Fairchild Mark IV (cartridge

Technicolor Model 500 (cartridge load .. sound) silent). Super8-mm, Rear Screen Technicolor Corp., 1985 Placentia ". Not available as single unit; must Ave., Costa Mesa, Calif. combination unit; see papa Fairchild Mark V (cartridge load 0Ond).' iinin, Front Screen Fairchild Camera and Instrument 1' Bauer P-6 Auto load, quartz Is bulb magnetic and optical sound. Corp., Industrial Products Dives le $1250.00 750 Bloomfield Ave., Clifton, 14:: 00 1 Bell and Howell Auto load 552 $755.00 Rolex 18.5, Auto load, silent .50 Sell and Howell 302-M magnetic sound $950.00 Supor4Imm, Front Screen Gratin Model 815 manual threading $625.00 Technicolor Model 510. (cartridge tRCA Safethreader No. 1600 .00 load, silent). *Eastman Kodak AV105mm ma Technicolor Corp., 1985 Placentia sound Ave., Costa Mesa, Calif. $ 99650. Victor Mag-3 magnetic sound Eastman Kodak M90 Reel load, silent. Eastman Kodak Co., Apparatus and Special Purpose Projectors Optical Div., 343 State St., Roches- Megnetic Sound Technicolor Model ter, N. Y. $1 ;09projector. No. TMT 25 telassil$41 EnStrnan Kodak M00 Reel load, ikelert Soundstrip 35mM 'OritintIC 'Sound filmstrip. n Kodak CAI The Mint Co., inc., Huftenkrs'Sti Optical Div., 343 Stet, 'Caw 6.N. Y. Bauer T1-S, Quartz ,Impot C0114. Sq9 Perk 104,041r#,Y*&* Yt: ?' *II and Howell the!i, Selo Ce,1100,A*Cermikked, Chiceip, afi

sound can be. addif, tape recorder liOnoflax, Inc.. 3730 Monroe Ave, Rotheito, KY. 4,,,Ftltro Co". l'reet. end Cooper OM. OW SWOON . 1P4,0 SOO 0011$0i0 VI 10111000,,1004fritdalallineit.iiii* Yedt

27 classroom use of filmsand projectors.The home cilitate immediate 8mm front (wall) screen simplified operation, and im- variety of projectorswhich utilize regular 8mm film segments. The suitable for front screen proved picture, will be ofinterest to those who film generally are not models. Auto-load- projection in classrooms.The Bo lex Model 18-5 have not examined the new high quality pro- ing characteristics aresuch that the inexperi- ($200.00) is an example of a teaching assistant can get a been used successfullyfor this enced instructor or jector which has of seconds with the cartridge loading projec- picture on the screen in a matter purpose. Among minimum of training.Examples of tors, the TechnicolorModel 500A offers an in- an absolute expensive regular 8mm projector( $85.00) with this equipment include: still picture capabilities,without sound. This Bell and Howell Autoload projector takes afour-minute cartridge. The Model 552 $ 755.00 manufacturer indicates that itwill give a satis- darkened room RCA Safethreader Model factory 30" by 40" image in a 1600 "Safethreader" $ 617.00 on a wall screen.It has been usedfor front screen projectionin small areas undercarefully Graflex Model 815 (manual loading projector) $ 625.00 controlled conditions. Bauer P-6 Autoload,incadescent or quartz 12projection bulbs available 51250.00 The following projectorsoffer a combination of optical and magneticsound reproduction features. They also have afeature which permits the user to add his ownsound track to the film ( magnetic recordingfeature). Bell and Howell Filmsound302 M $950.00 Eastman Kodak Model AV-105M$885.00 Victor Mag-3 $670.00

A comparison of regular8mm, Super 8mm and 16mmfilm formats. The shaded areasindicate the space availablefor the sound tracks. Super-8mm front screen projectors.Here the teacher has a choice ofsupporting models with improved light sources andlenses. The Eastman M-90, reel type ($180) orthe Bauer ( $179.50) are examplesof Super-8mm prcfectordesign. The Eastman M-100projector has magnetic sound capabilities, and, inoperation, offers suitable performance inthe small classroom. It is comparable in price to 16mmsound projectors. The Technicolor 510-A($90.00) is the only Su- per-8 cartridge loadprojector on themarket at present. It has nosound capability andtakes a four-minute cartridge. 16mm front screen projectors.Considerable improvements have beenmade in loading characteristics and light outputof 16mm sound projectors in recent years.These improvements fa- A Technicolor projector andfilm cartridge.

28 I

Sound conversion units are available to provide Light sources.The General Electric Mark magnetic sound recording and playback capa- 300 high intensity light source, available in many bilities for existing equipment. The Gregory new projectors, so increases illumination on the Sound Conversion Unit sells for $195.00 plus screen that film can be shown under normal installation. For a discussion of magnetic and classroom lighting conditions. optical sound, see below. When considering the purchase of new pro- 8mm rear screen projectors.A self-contained jection equipment which might be used in a rear screen and projector for 8mm film resembles large lecture hall, suppliers should be given the a small television set. The advantage of rear room dimensions, lighting conditions and other screen projection is that it can be used in the features in addition to the projector capabilities normally lighted laboratory or classroom. Cur- desired. All such equipment should be tested in rent model projectors take cartridged film. They the rooms in which it will be used before a pur- are extremely simple to operate requiring a min- chase is made. imum of maintenance. The only projectors of Rear screen projection cabinets.Good com- this type now offered in the regular 8mm size, mercial rear screen projection cabinets are avail- are the Technicolor Model 600AD ( $250.00 ) able for use with a variety of projectors running and the Fairchild Corporation Mark IV projec- from 35mm slide to 8mm and 16mm movies. The tor ( $495.00 ). The Technicolor projector uses Hudson Photographic Industries 8mm screen a four minutes cartridge; the Fairchild projector ($17.00) and the H. Wilson Corp. 16mm screens takes a cartridge which holds up to 22 minutes ( $150.00) are examples. For the the "do-it-your- of color film. Magnetic sound is a standard fea- selfer," the Eastman Kodak Pamphlet No. S-29 ture with the Fairchild projector. Color prints REAR PROJECTION CABINETS offers excel- of the CHEM study films are available in cart- lent directions on local fabrication. ridges for Fairchild projectors. One model of the projector is equipped with a magnetic re- Sound characteristics of film.Conventional cording feature ( model IVAV ). 16mm sound film has an optical sound track in which the sound reproduction is stimulated by 16mm projectors for rear or front screens. The light. Films now can be supplied with magnetic Kalart-Victor projectors use regular 16mm film sound tracks. Here the sound reproduction is in combination which provide both front and stimulated by the interaction of a magnetized rear screen projection capabilities. stripe on the film with a charged head in the projector. The magnetic sound stripe similar to 441111.1,tas. that on an audio type can be added to film prior to photographing. Sound can be recorded as the film is exposed in the camera, or it can be added later using projector with a magnetic recording capability. Eastman film, Kodachrome II No. KA558, can be ordered now from dealers. A camera suitable for this use is discussed on page 31. Probably more important to the teacher is the fact that 8mm, Super-8 and 16mm film can be shot silent and the magnetic stripe added when the film is processed. This affords the opportunity of adding a sound track to the film as it is run through the projector. Magnetic striping makes it possible to add a second sound track to films with sound. Magnetic sound tracks can be erased and corrected as with an audio tape A Fairchild projector and film cartridge recorder. 29 TABLE F-7

; ,

schools. Contact the effects, prints from A and Brolls,minimum charges, or discounts to Prices do not include costsof internegative, printing laboratories for specifics. TABLE F-8

'e, it Offering 8mm *w

Calvin ge W. Colburn 111 Aklboratory, Inc. R° 44North Wacker Drive 141,01*. Chicago 6, Illinois

Ol4Ouvirne stories L4Xe Laboratories, 4076 Transport Street Tenth Avenue `,.:*t York 19, NewYork Alto, 'C01,060114% 940

Oral Film Laboratories 1546 N. Argyle iywood, California

lywood Film Enterprises# Sunset Boulevard

30 &

Inquiries concerning magnetic striping proc- the usual low light situations encountered in the esses and costs should be directed to the film laboratory. processors. Still projection systems.Several new still pro- Film costs.For those planning to make their jection systems which have appearedrecently own films, Table F-7 gives approximate current are described in thefollowing paragraphs. costs for the printing of silent color films and for Filmstrip with magnetic sound.The Execu- addition of magnetic sound stripes. Table F-8 graf ( $375.00) uses a film and a sound cartridge: lists some laboratories offering release print the film cartridge contains up to one hundred service. 35mm pictures, and the continuous loop sound Cost of cartridging films.Cartridge costs tape cartridge has a running time up to twenty range from one to ten dollars ( based upon the minutes. This projector has both the front and kind of projector and on the quality ordered ). rear view facility. Technicolor Corporation now will furnish and Filmstrip with optical sound.The Kalart load cartridges for their projectors at a cost of Sound strip projector ( $400.00) uses a continu- $1.00 when suitable 8mm film is furnished. Cart- ous strip of filmidentical with a sound movie ridges for the Fairchild projectors cost from $6.60 except that the picture and the accompanying to $9.95 and special film treatment for films longer sound track are printed on alternate frames. Pic- than 200 feet is necessary at a minimum cost of tures, or slides with accompanying narration on $4.00. Those desiring to have films put in cart- audio tape can be sent to the manufacturer for ridges are encouraged to contact the Techni- conversion to this format. color or Fairchild Corporations directly. Slides with sound.The Hughes Video-Sonic Cameras and lenses.Accompanying the intro- ( automatic control ) projector Model 901 duction of the new film formats and projectors ( $400.00) is a self contained rear screen projec- are improved cameras.Cartridge loading of cam- tor which accepts 35mm slides in 36-slide trays. eras with Super-8 film is simplified since the cart- It has magnetic tape for audio. ridge need not be turned when half the footage Audio attachments for slide projectors.In film has been exposed. Zoom lenses permit going many cases it is possible to use existing equip- from a wide picture to a close-up and vice-versa ment, or combinations of projectors and record- without stopping or moving the camera. Reflex ers, to generate automatic presentations of slides cameras with "through-the-lens" capability al- and sound. The Kodak Carousel Sound Synchro- low precision composing and focusing of close- nizer( $20.00) enables the instructor to com- ups. For photographing close-ups of laboratory bine a stereo tape recorder of any type with a equiment or reactions, cameras with a retail Carousel Model 700 or Model 800 projector. price of $75.00 or less probably will not give Slide-change signals are recorded on one chan- acceptable steady picture quality. nel and the narrative on the other track. On Two professional cameras which are available playback, slides change automatically; this sys- for 8mm film are the Bolex H-8 ( $480.00 ), and tem is easy to connect and use. the Pathe DS-8 ( $900 ). The latter is the first A synchronized sound-film system.This is camera to use a 100 foot double Super-8 film available for the Technicolor Model 800 Projec- spool. The Fairchild Model 900 ( $900) is now jector, from Ealing Films or Auto-Sell, Inc. on the market as a regular 8mmsound motion ( $255.00 for projector and recorder ). Both tape picture camera. and film automatically stop when the end of the Plastic lenses are excellent for some uses; film loop is reached. It is possible to program the however, experience has shown that glass lenses film loop for double or triple showing, using are more suitable in close-ups for chemistry up to 20 minutes of narration. uses. Cameras with fastlenses( aperture not Special effects.The Kodak motion adapter greater than f/1.9 and able to accept accessory unit ( $24.00) consists of a spinning polarizer close-up lenses are a necessity for quality film which fastens on the front of any 35mm projector makeup. Slower lenses restrict camera use in lense and requires especially made slides which

31 111111101,

.111. general considerationsof student comfort contain elements ofpolarizing material. An effec- in the lecture roomincluding light control, tive motion illusion ispossible including continu- adequate sound facilities,and seating. ous orcyclic movement, rotation,vibration, and Inc. can pre- For the optimum useof projection during a radiation. Technical Animations, be a minimum of equip- slides on a custom basis.The Ameri- lecture there should pare motion adjustments. For allpractical Book Company will be thedistributor for moment and facility can should be in a fixed position tion slide series.Eastman Kodak,Audio-Visual purposes, the screen orders for slides. Experi- away fromdirect light sources andfrom areas dealers, will handle avoid if possible a mental kits of TechnicalAnimation polarizing used more frequently, e.g., location where a roll-down screen covers materials are also availablefrom the dealers. screen vibration modes of the chalkboard. Prototype slides showing the instructor should molecules now are available. Under ideal conditions, be able to push abutton and insert into thelec- Random access slide projector.One of the ture a film orslide for seconds or minutes as disadvantages in using slides to augmentlectures needed, with absolutely nomechanical distrac- order of has been that thelecturer is tied to an tions to the class. projection not easilychanged. This disadvantage The screen is mostoften the appearance on themarkt Projection screens.' is overcome with the projection systems. 35mm automatic slide pro- the weakest link in using of random-access, which the screen can trans- jectors, such asthe Dial- A-Slide projector The efficiency with mit color brightnessand contrast to the eye, ( $700.00) or EastmanKodak RA-950 projector which the point being have controls which affects the ease with ( $785.00 ). Both projectors by the student. Follow- projected. made can be understood tell the instructorwhich slide is being discussions of screen typesand Similar units are availablefor connection to ing are brief their suitability toclassroom or laboratory ap- data retrieval systems. plications: UTILIZATION OF PROJECTEDMATERIALS Matte screens.Matte screens diffuselight Regardless of the qualityof a motion picture evenly in all directions.Images on matte screens viewing film or slide, or theadvanced state of the art in appearalmost equally bright at any hardware, successful projectiontechniques re- angle. To avoid distortionbecause of viewing main the key totransferring ideas and concepts angle, however, viewersshould be no more than from the projected image tothe students' mind. about 30 degrees to the sideof the projection than two-image widths to By following goodpractices in setting up aclass- axis, and not closer room orlaboratory for the showingof film, the the screen. instructor gains theultimate flexibility for utiliz- Most matte screens areabout 85% efficient. ing a slide or film clip inthe lecture with the con- A metal finish matte screenwill give valuable fidence that the class will receivethe maximum color correction to pictureswhere true rendition be a benefit from the medium. is important. Aform of matte screen can although it should be This section is intended tohelp clarify some smooth wall painted white, viewed critically before acceptingit for class- of the steps necessary to insurethat the message reaches the class withoutinterference by the room use. These screens have a reg- projection process. Lenticular screens. ribs, rectangles, or dia- the classroom, con- ular pattern of stripes, For effective projection in mond shaped areas. The patternis too small to sideration should be given tothe following: see at viewingdistances for which the screen is selection of a screen location, size,and type. designed. The screensurface may appear to be selection of the optimum projectorlocation. enameled,pearlescent,granularmetal,or providing required imagebrightness. smooth metal.

*Most of the information on screens wastaken from Eastman-Kodakpublications.

32 By control of the shape of the reflecting sur- Shortened projection distances are claimed faces, the screen can reflect nearly all the light as an advantage by proponents of each system. from the projector evenly over a fan shaped area While this is true in both cases, a short projec- 70 degrees wide and 20 degrees high. Many tion distance often does not give the image lenticular screens provide an image three or sharpness and brightness desired. However, four times as bright as a matte screen. when space is at a premium, short projection Beaded screens.Beaded screens are useful it distances may be necessary and the equipment long narrow rooms or other locations where most can be made to perform adequately. viewers are near the projector beam. They are Visibility in lighted areas also is claimed as an white surfaces with imbedded or attached small advantage by proponents of both front and rear clear glass beads on silica chips. Most of the projection. Either system will do a good job, light reaching the beads is reflected back to- depending upcn conditions. When a small image wards its source. Thus, a beaded screen provides ( up to 3 feet wide) is desired, a dark colored a very bright image for viewers seated near the rear-projection screen may provide dramatically projector beam. As a viewer moves away from better image contrast and color saturation than the beam, the image brightness decreases. At a front-projection screen. Although a rear-pro- about 22 degrees from the projector beam, the jection screen reduces image brightness, the image brightness on a beaded screen will be amount of room light reflected toward the audi- about the same as that on a matte screen. Be- ence is reduced by an even greater factor. The yond this angle it will be less bright than on the back of the screen must be shielded from stray matte screen. Students should sit no closer than light. Front-projection screens always must be two and one half times the image width from a shielded from direct light. beaded screen. When a large image ( wider than 3 feet) is desirable, front-projection systems using a lenti- Rear - projection. Rear-projectionpictures cular screenusually give better results than have the same requirements for image brightness, rear-screen systems. Location and control of size, and contrast as front-projected images. Rear room lights are important factors to consider projector screens are made of glass, plexiglass, here. In any case, more care must be given to or flexible plastics with one side of the screen a the orientation of the projector, screen, and au- matte surface. dience than is necessary for a smaller rear-pro- To reduce space requirements in rear projec- jected image. tion, short focal length lenses sometimes are used. A single mirror between the projector and Screen Size.This should be such that the the rear screen is necessary; however large mir- back row of viewers is no more than six times the rors must be avoided. A special lens with a mir- image width( W ) from the screen, with the ror encased and suitable for this purpose is avil- following exceptions: able from Buhl Optics. a. Certain materials, including many teaching With most projectors. images as wide as 42 films, are designed with titles and import- or 48 inches will be satisfactory on a dark rear ant picture elements bold enough to permit projection screen in moderately lighted rooms. satisfactory viewing at distances of 8 to 10 For larger images, a light screen in a darkened times the image width. When this is true room is usually needed. In very brightly lighted for the materials to be projected, the pro- rooms, images should usually be no more than jector may be moved closer to the screen 24 or 30 inches wide and the screen material to give a smaller and brighter image. Mov- dark. ing the projector enough closer to change Front vs. Rear Projection.In considering the back row from 6W to 8W will approxi- which projection system is best for given condi- mately double the image brightness and al- tions, two common arguments regarding both low the front row to be moved a little systems are discussed below. nearer the screen. 33

VC1111U.0141**"."." =1,

b.In some situations, materials whichlimit screen from the projector.Foot-candles of illum- maximum viewing distance to less than 6W ination multiplied by the reflectanceof the screen are commonly used.Typewritten material ( about 0.85 for a good mattescreen) gives in projected with an overhead projector is an foot-lamberts, a measure of the brightnessof the example. For showing the full area of an image seen by the viewer. 8.5 by 11-inch page, pica type calls for a Thus, a projector with a 120-lumen output maximum viewing distance of 3W.The provides 10-foot-candles of illuminationfor a teacher should critically test this for his 3 by 4-foot ( 12 squarefoot) screen image; that particular situation, perhaps by taking the is, 8.5 foot lamberts of imagebrightness for the poorest seat in the classroom. viewer of a good matte screen.With a projector A discussion of screen size with excellentsolu- light output of 80 - 100 lumens,and a matte tions to common puzzles is available inEastman screen in awell-darkened room, an image 3 or Kodak publication Effective Slides S-22,and 4 feet wide can beviewed easily. As a rough Legibility Standards for Projected Material, S-4, estimate of the imagebrightness required, there and in the ACS publication, How toMake should be as many foot lambertsof light per of Slides. square footof screen as there are foot candles Image brightness.Required brightness ( the light in the room. For a moredetailed discussion amount of light the student sees)depends on of image brightness seeEastman-Kodak publica- viewing angle; screen type; projector design, tionS-14 "What Can You DoWith 100 wattage, life rating, and age of lamp;character Lumens?" of material being projected; image size; line Projector location.Optimum projector loca- voltage; as well as on the design and cleanness tions depend upon a varietyof factors including of the optics. Lamp wattage alone gives little the lens and the screen size. Mostmanufacturers indication of image brightness. Using wattage of projectors as well as lens suppliers( Buhl Op- as a measure of imagebrightness is comparable tical Company) can provide awide range of to rating an engine by the fuel consumedrather lenses for any type of projector. Todecide on than the work done. the lens needed for a given projectorand situa- The effectiveness of a projector, expressed as tion, one should first determinethe size of the image brightness, is defined in termsof lumen screen to beused and then with the aid of a output. Lumen output dividedby image area ( in table such as Table F-9, the correctfocal length square feet) givesthe foot-candles falling on the for the lens can be calculated.

TABLE F-9

D e t e r m i n i n g P r e j e c t i o n D i d i: n c e , Image Widt lio'orLetts

, 4 i. 1 tirMinethe 'projectiondistance a desiredimage width (orthe imaleWidth for e desired *On-distance), lisitinthefollOwing table the factor that apptieS tothe fl m farina 'and teni, tau '*re 1;i0singiTnen ion a 'Oraightedge Minthe nomograph"sothat the edge *Sit through the oUA other Iftgure at. the a where the , , ,:1ithi,.,. ..., ,. , Ltittlie len

, , rgillitle desired OroleitOOn'7-

41 1MS I length; position the straightedge so that it Passthrough the des OW that ja .0 t

,04 1111111111111010=warmosnr

. . ) )

,.,. 16mm Motion ,,, I?... Pictures 4.t. 2 x 2" Slides ., Ls G. (0.284" x 0.38" 246 (38mm square or :/ 4.7 r projector mask) 3 7.9 20-2,A381001, 9 tt) ri .:, 4 Oliaik) 1 7A .;,,1 Super 8 Motion m ;1 (28mm) 5.2 .6) , 2/ 04.0 Pictures 4, , '...... ili4;'04160...... "--" (0.158" x 0.2h- Zoom et..32mrro3.7 6.0 2,9 projector mask). 2 x 2" Slides '''s4 3.8 . h A (26.5mm squareL.- ,46.1 enitn Motion .-.. 4A 3A mask) Pictures -74 (22mm) 5.0 (KODAK ,8.7 (0.129" x0472" Zoom projector mask) (15 - 25mm)34 - 5.7 INSTAMATIC) . s 10.5 illmstrip 3 3.3 6 .8- 5.7 4 4A k, \ i (172 x 23.00m) , 2:2 5 5.5 Lantern Slides .., projectedarea) 7 4.0 7 .7 (Maskopening 16 ,-5.3 3" wide) 2.3 26 3.0 ii\ i Overhead and 2 x g" Slides , , 3.7 14 ,.. Opaque (231 34rnin 7 5.2 18 horizontal mom) 9 6.7 (Material10' wide) t ''11 8.2 .

Zoom . (4 -,6) 30-4.5 , .

Proliction RAW Diana Width (fist) Onehm)

100 00-- 10 70- 1. - 60 6- SO- 40

WI 3.-

*Reproduced through permission of Eastman Kodak.

35 Mnr7,..7,rwm7,777,,,,,,,,,,,,.

FIGURE CI-1 Computer assisted instructionpermits many of the student- teacher interactions whichpresently occur on an individual basis (a) to be captured (b)and expanded for a multitude of students (c). iob

COMPUTER ASSISTED INSTRUCTION

Generally, the modern high-speed computer Indeed, it is even possible to provide an audio is considered to be an instrument used primarily statement by the computer, if required. in the solution of complex numerical problems Since a computer is capable of making a series or the processing of large quantities of data in of decisions and initiating actions based on these standard ways. There have been many reports decisions very rapidly, it is possible for a single of the use of both digital and analog computers data processing unit to handle more than one in chemical education. However, it is also pos- student terminal at once. At present, up to 32 sible to use computers to supplement teaching students can interact simultaneously with one techniques. This report concerns itself primarily computer. The number of students is limited by with these "non-classical" uses of the computer. the sophistication of the computer in which the Computer assisted instruction ( CAI) can be program is stored. The capability of a given in- defined as a Socratic dialogue between a student stallation is not totally reflected by the number and his teacher with a computer as an inter- of time-shared terminals, since the latter can be mediary ( Figure CI-1).In essence, the com- scheduled for student use at any hour of the puter serves as a medium to capture the way a day. In addition, computer terminals need not teacher approaches his subject. His particular all be placed in one location but may be situated point of view, his bias, as well as the pedagogi- in various convenient locations._ cal nuances he normally employs in teaching his Student responses in the dialogue are not nec- subject, all these can be stored in the computer essarily restricted to fixed phaseology since the to be explored at will by one or by a hundred computer can be instructed to search for key students. words in the students' portion of the dialogue. EQUIPMENT Mechanically, student responses may be either Basically, the computers used in CAI are very typed on a typewriter-communication ,snit, or fast data retrieval systems which include ( Fig- the student can communicate with the computer ure CI-2 ),( a ) a central data processing unit, by means of a light pen pointed at a specified por- (b) large capacity data storage units,( c )a tion of a cathode-ray tube. transmission control ( oi traffic regulator) unit, ( d ) other peripheral devices which may be associated with the system but which need not be discussed at this point. The CAI system is designed to receive a set of sequenced instructions and perform them automatically. These instructions can be given to the system by either a typewriter communication unit or by standard punch cards. The former method is usually used by authors intially composing programs. Card Reader That part of the dialogue supplied by the computer is not limited to single words typed Information Transmission by a typewriter terminal under the "control" of Storage Data Processing Control Units System the computer, although this is currently the pre- Unit dominant mode of presentation. It also may consist of slides or motion picture film illustrating _L_ the results of a laboratory investigation, an excerpt from a book, or any other material, re- Multiple Communication Unit stricted only by the imagination of the teacher FIGURE CI.2 who prepared the program and the capability A conceptual diagram of the basic units which make up a of the hardware available to him ( Figure CI-3). typical CAI system.

37 1.

purchase it outright I equipment rather than to since all of the units in a system areconstantly being improved. For those personsinterested in a more modest approach toCAI techniques, terminals connected to computerslocated as much as several hundred miles away canbe rented.

PROGRAMS The construction of a programfor CAI is not difficultfora skilled,experiencedteacher, though it is time consuming andhas some tedi- ous aspects.The techniques needed often are similar to those used in writingprogrammed instruction ( 4 ). prepared by con- FIGURE CI.3 In essence, a program is A typical communications terminal for aCAI system. The structing an imaginary conversationin the form computer can present information or questions tothe stu- of a flow chart ( Figure CI-4)between a student dent by means of a printed output or byvisual displays and a teacher. The teacher mustbe continuously (either on a cathode ray tube or with a slideprojector) while the student may respond to the computer with atypewriter aware of exactlywhat he intends the student to or a light pen. learn in detail and of the guiding statementshe whose responses In summary, the author of CAImaterial types would make to help a student In the construction his program into the computer,specifying infor- suggest a misunderstanding. mation, questions, anticipated correct or wrong process, the teachershould assume that typical flow of the sub- answers, and actions tobe taken by the com- students will deviate from the teacher, therefore, puter for a given student response.The program ject in a variety of ways. The of corrective comments. is constructed using standardoperation codes. must compose a variety dialogue with the The computer stores the program andperforms Often these consist of a short the operations designated when thestudent in- student within the overall majordialogue. While code-word and teracts with the CAI system.It is also possible the dialogue is being composed, for the system to provide a recordof student format instructions to the computer areadded. which can be used by the author in For example, the function"wa" in the Course- responses that the next fol- refining the program. writer language ( 5) specifies At present, only the InternationalBusiness lowing sequence of words is ananticipated Machines Corporation offers completelyinte- wrong answer to apreceding question. This the grated CAI systems( 1,2 ); however several function causes the computer to compare specially designed installations exist which con- student's response to the questionwith the match be- sist of central data processingunits and associ- words which follow the symbol. If a and the author's ated equipment manufacturedby a variety of tween the student response companies (3). All of the major computer man- statement is obtained, the computeris directed ( or action ufacturers are in the process ofdeveloping CAI to make an appropriate statement systems. Personsinterested in exploring the e.g. change aslide ). If no match is obtained, a possibility of incorporating CAI techniquesinto different action is initiated. by their teaching should contactrepresentatives of Programs are entered into the computer terminal. After suit- the firms that service the dataprocessing equip- the author at a typewriter ment already available attheir institutions, be- able preliminary planning [such asconstructing efficient cause of the veryfluid situation which exists in a flow chart( Figure CI-4 )], it is most the terminal from the design and productionof CAI systems. Also, to construct the program at it probably would beadvisable to rent CAI notes. Once the programis constructed, inser-

38 tions, deletions or modifications of almost any Not all of the probable responsesneed be kind also can be incorporated into the program predicted, since the development of agood from the typewriter terminal. ( See Reference 1, working program usually involves refinements 2, and 3 for details concerning terminalconfig- based on student use. Even a typical student re- urations.) This procedure usually is necessary sponse can thenbe accounted for in construct- since the teacher's imagination and experience ing a generalized computer statement tofollow often are not sufficiently percipient to encom- the response. Further, it appears in most cases, pass all but the more commonmisinterpretations that though the phraseology, or style, ofstudent and outright errors a student will make whenhe response varies,students tend to use a reason- is confronted by the program. Using aterminal ably small number of different, usually synony- in this way, the author can switch to"student" mous, key words. Hence,with experience in the mode at will, testing out the logic and responses preparation of instructional programs, the diffi- incorporated in the program as it is written. culty in anticipating student response becomes Several published examples of CAI programs lessened. are available(6). Since the only readily available language (5) The validity of CA/ as a useful tool in teach- for CAI programs does not commit the teacher ing is perhaps best illustratedby an example. to any particular teaching method, it ispossible The flow chart in Figurt CI-4 illustrates the ap- to incorporate a variety of teachingtechniques plication of CAI to a chemical topic. This chart permitting him to retain originality in his pres- shows a portion of the logic for a program which entation. Thus the success of the program is is to be used with laboratory work oncolligative limI ed by the ingenuity of the instructor. Pro- properties. The computer responses are given grams can be written thatessentially represent in the boxes with rounded corners and the stu- data retrieval systems in the worst sense of the dent responses in the squared boxes. Inspection word, i.e. a series of questions is asked by the of this flow chart shows that a varietyof path- computer and answered by the studentwith lit- ways al e available tothe student as he proceeds tle interrelationships among successive ques- through the program. It must be stressed that tions and answers. Alternatively, the program no attempt hasbeen made in this flow chart to can reflect arich dialogue between a sensitive provide for equivalent or key word responses. teacher and an inquiring student with the com- It should be noted that the statements( Fig- puter merely acting as anintermediary. It seems ure CI -4) from the computermatch the preced- evident that program authors should also be ing responses of the student. In the construction competent,experienced,modernchemistry of a program, it is necessary, in principle, to teachers, or at least such individuals should be anticipate every possible response a student associated with the deveolpment of chemistry might make and to instruct the computer to pre- programs in CAI.Although CAI systems have sent suitable statements( as determined by the not yet received wide acceptance inchemistry, teacher-program author) to any response made those anticipating t1-.e use of CAI techniques by an individual student. In practice, of course, should exercise caution in purchasing commer- this is impossible. Thus, in preparing a program, cially prepared CAI programs and should assure the teacher does the best he can to predict the themselves that the contents represent modern several probable student responses to each state- chemistry standards by requesting to see flow ment in the program, ;ALAprovides the corres- charts of the programs before hand. ponding statements which should be made to Computer-assisted instruction can be adapted each response. In these cases, one is not con- to the aptitude of the student in analmost hu- cerned with the phrasing of the students' re- man way. For example,if the student repeatedly sponses, but only withkey words in the response makes a wrong selection of possible answers, the which the computer identifies as the clue tothe computer statements could be madekind and next statement that shouldbe presented to the patient at first but after several such responses, student. more stern comments orsuggestions for more 39 The student has finished a laboratory experiment on colligative properties of solutions; in particular he has performed an experiment on the freezing point of a solution of acetic acid in Wane.

Well, now that you have completed the experimentalwork on colligative properties in the laboratory, perhaps we candiscuss your results. In considering the useof colligative properties such as the freezing point depression of asolution to determine the molecular weight of a solute, what factors affect thefreezing point of a solution?

(Any other response) The amount of solute The amount of solvent The concentration of solution (or) The concentration of solute Since we are dealing with solutions, it might I be well to consider var- What concentration units are usually iablesthatcanbe usedwhendiscussingcolligative measured. Try again. properties? The amount of solvent The amount of solute

Fine, how are these two factors related?

Correct. The freezing point Remember, the molality is deter- depression of a solution is mined from the volume solvent Good, therefore the colligative prop- related to the molality of the which is a function of tempera- erties ore dependent upon the con- solution. Using the value of ture. Considering this effect what centration of the solution. What con- 5.0 for the freezing point de- concentration unit would be more centration units are usually used pression constant for ben- appropriate for our purposes? when discussing colligative proper- zene, calculate the molecular ties? weight of acetic acid from your data and enter your answer.

(any other answer)

any other number) (a number between 55.65) (a number between 115-125) You are apparent,- having difficulty with concentration units. Study the sec- There appears to be an Your molecular weight The molecular weight appears to tion on concentration units error in your calcula- appears to be too low be compatible with the data, how- and on colligative proper- tions or in the way you foryourexperimental ever it does not appear to support ties in your text before you collected your data. data. Please recalculate. the usual formulation of acetic proceed with your experi- Check these two acid, i.e., CH3CO2H. Give an ex- ment. Please sign off. points.If the results planation for this discrepancy. are the same please sign off and see your instructor, if not, enter your recalculated answer.

Exit to a discussion of the hydrogen bond.

FMK C14 of a flow chart for a program on colligativeproperties and hydrogen bonding. Many of the MOM Iftyphrimit for ,latiahroleat Stadent rigors" and key responses have been omitted for ,,Oreeeld,oftt dOehod Hof( - intense study of the topic could be programmed some repetition of technique is essential, over- into the computer. Conversely, if the student exposure may detract from the learning of data does well, the statements of commendation can handling and the understanding of principles. vary, at one time calling the student by his last To minimize this, CAI methods can be em- name, but with a compliment attached, and on ployed to provide( a) supplement laboratory another occasion with a short complement and experiments to give him experience in manipu- the student's first name. There is evidence to lating laboratory data or ( b ) simulate labora- suggest that some CAI programs have failed to tory experience before the student enters the teach well because the teacher-program authors laboratory. Each of these represent legitimate have used stilted, formal phrases in the state- uses of CAI when properly applied. ments they prepare for the computer to store For example, the student can be assigned to and present to the student. A computer can do conduct a trial titration at the computer ter- only what it is told to dol Hence, the statments minal either before or after he has had labora- generated by the computer for the student can, tory experience. In this instance, the computer and perhaps should, have a personal quality in may ask the student to decide upon the prepara- many instances. Similarly, trite responses should tion of a primary standard ( or, it can just as be avoided as they are not in the normal stu- readily ask the student to identify the first step den -teacher interaction. of the titration instead of naming it for him ). THE USE OF CM IN CHEMISTRY The student then selects a primary standard, In some of the literature on the subject, it has and the approximate amount of the substance to been suggested that CAI can, and will soon, be titrated, whereupon the computer gives the replace or minimize the independent utilization student the precise weight of the sample. Next, of many of the more familiar teaching tools. the students decides to use, say a 100m1 volu- Other opinions dispute such claims, and support metric flask, and the computer responds by in- the contention that CAI can eventually become dicating that the quantity of sample weighed another important and versatile tool a view will not dissolve completely in this amount of supported by this report. The following brief solvent, whereupon the student will either have descriptions of different possible uses of CAI to decrease the sample size or increase the size ( only a few of which have as yet been even ten- of the flask. Afier more of this kind of dialogue, tatively explored) will indicate some of the eventually the student simulates the preparation ways in which this technique might prove useful of his solution and arrives at the details of the in chemical education. titration. At this time, utilizing pertinent data Laboratory.In the laboratory portion of a and a generalized program ( which would not course, students are usually expected to acquire necessarily be prepared by a teacher-program some manipulative technique as well as a facility author, but would be available to him as a sub- for handling experimental data. Thus, a tech- routine by calling for it with a code word in a nique may be taught in the laboratory( e.g., Fortran-like computer language ), the computer titration) and then the technique may be be- would calculate the pH of the solution for each labored endlessly to show the student how it increment of titrant added by the student. The may be used to obtain experimental results di- data thus provided could be used to plot a titra- rected to a variety of ends. For example, it is tion curve and to calculate the concentration of not uncommon to have students do acid-base titrant. titrations, equivalent weight titrations, oxida- It is possible to write a program that incorpor- tion-reduction titrations, etc. However, all these ates the experimental error expected for the experiments involve a basic titration technique equipment normally used in this type of experi- and the student usually spends more than a few ment. In this case, a second or third computer- afternoons doing essentially the same thing, generated titration curve using the same sample each time for a slightly different reason. While would give a similar but not identical answer!

41 In further dialogue, the studentcould now elect to insert amendments to correctsuch deficien- always be neces- to use his simulatedstandardized solution in an cies as they occur, it may not appropriate way. For example, asimulated un- sary or desirable todo so. That is, at some points known acid could be computer-titrated withthe in a dialogue, with the computer,the student standard solution and the pH of theunknown may reach animpass, i.e., a pointwhere no obtained from the computer for each increment statements in the computer aresuitable for his of titrant. The student would then beasked to response. Insuch a case, the next computer plot his data and calculate the equivalentweight statement can advise thestudent to see his of the acid. Another sub-routine couldsimulate teacher personally and even set up anappoint- a deteriorationof a standard solution, if this ment for him ). The computercould even advise were chemicallyrealistic and desired by the the teacher that this particularstudent has un- teacher-program author. The limitations of this derstood a topic up to a point, brieflydescribe type of application is by no meansrestricted to the point giving difficulty, anddescribe the next titrations, but rather reside in thelimits of the point to be covered after thedifficulty is elim- imagination of those who participate inthe inated. With thistype of information, the preparation of programs for CAI inchemistry. teacher can, with less time involved,help the and send A different kind of laboratorysimulation in- student over the hurdle personally, for further corporating visual presentationcontrolled by the him back to the student terminal computer is applicable toqualitative analysis dialogue :here. (7 ). In this instance, the student sees on a Evaluation of student ability and progress. screen a picture of anunknown solution in a While the student is at a terminal,responding to beaker, or perhaps in a test tube. After a dia- the statements he receives from the computer, a logue with the computer which terminates in record of individual student responses in sum- the student's deciding which, and howmuch, mary form can bemaintained by the computer reagent to add, the next pictureshows the re- for the teacher. Later, when usinganother pro- sults of the addition. Then the studentmight gram, the computer canreadily indicate to the select a separation of a precipitate and a decant- teacher that a student has, or has not,demon- ate, say by filtration, and aftertelling this to the strated an improvement in his proficiency inhis computer, the correspondingslide appears and studies as measured by a change in responses to shows the results. Obviously this mode of in- perceptive answers to the computer statements. struction would require the preparationof the It has been proved to be possible to generate slides in advance. Currently, a maximum of 1000 individualized quizzes on subjects that lend slides can be stored in a random access projec- themselves to this technique. Thus, with CAI tor and their rapiddisplay controlled by the equipment it is possible to construct a s .of computer. examinations on which the student must rearh These examinations would 7 ie CAI provides an ideal me- a specified level. Tutorial assistance. available on demand when the student feels he dium for the presentation of tvtorial,drill, or has mastered the material. The computer pro- remedial material in subjects Ihere the onusin rapidly shifts gram can generatethe examination, grade it, the teacher-student relationship inform the student of the results, andkeep a from the instructor teaching to the studentlearn- ing. Stoichiometry, balancing equations,and record of the grade. formula writing represent a few of the moreob- Incorporation of other material.It should be vious subjects for initial CAI programs in gen- clearly understood that few students can toler- eral chemistry. It is not possible, ashas been ate long sessions at a computerterminal, even suggested above, for a teacher-programauthor though the statements presented by the com- to predict all of the possiblekey words and sy- puter may be lively and provocative on occa- nonyms that might appearin the rerponses of a sion. For this and other reasons, it isdesirable to large number of students. Although it ispossible require students to seek help periodicallyfrom

42 .1.110141MIN.

liwrimmow.

more familiar sources.Thus, at an appropriate SUMMARY With the experience available now, itis evi- point in the program the computer statement be applied to could ask the student to leave the terminal and dent that CAI techniques can teaching a variety of topics inchemistry often seek information from his text, a reference inthe more efficientlythan conventional methods. library, or a brief experimental investigation, More importantly, thecareful application of querying him about his findings uponhis return. CAI allows each student toproceed through Students who are unable to indicate satisfactor- the subject at his own rate,reworking the ma- ily that they obtained the neededinformation terial as often as he feels is necessary.CAI may can be givenalternate, easier, assignments ( and free the instructor to teach topicsthat are more this fact noted in the record) or they can be difficult to handle or those that mayhave been asked to repeat the assignment. Any option omitted for lack of time. Although somemight which is elected by the teacher-program author be concerned that CAI methodsinvolve the de- and incorporated into the program can be em- humanization of teaching, it can beargued to ployed. the contrary that these techniquesprovide a method for more individualizedinstruction, a require the stu- The CAI technique can easily way of capturingthe individuality of a teacher dent to read and study appropriatematerial be- and preserving it for all students. fore he uses the computer. Forexample, after a It is apparent that CAI canbe more useful to period of study on a given topic,the initial com- those teachers in chemistry whohave computers puter interactioncould be a short examination. at their disposalif a method could be devised Based on the result of this examination,the com- for the efficient exchange of programs.To help puter could thenfurther instruct the student in catalyze this exchange, it is suggestedthat per- only those matters for whichhis answers were sons interested inexchanging ideas on CAI do Lagowski, Department of Chem- ,.) unsatisfactory. Completing this, the computer so through J. J. and the student could proceed to adialogue istry, The University ofTexas, Austin, Texas which develops the topic to thedepth desired. 78712.

43 REFERENCES AND FOOTNOTES ON COMPUTERASSISTED INSTRUCTION Proceedings, 1. International Business Machines Corporation, nual Industrial Engineering Institute "1500 Operating System, Computer-Assisted In- University of California, 1965; (g) J. A. Swets,S. H. struction, Coursewriter II, System Summary," White Millman, W. E. Fletcher, and D. M. Green,"Learning Application of a Plains, New York, 1966. to Identify Nonverbal Sounds: An Computer as a Teaching Machine," Journalof the 2. For a description of IBM CAI systems see, (a) Accoustical Society of America, 34, 928 (1962). G. J. Rath, N. S. Anderson, and R. C. Brainerd, "The 4. See for example, J. Young, J. ChemEduc., 40, IBM Research Center Teaching Machine Project," 11 (1963); !bid, 400 (1963) and referencestherein Automatic Teaching: The State of the Art, (E. Calan- der, Ed.) New York, John Wiley and Sons, Inc., 1959; 5. Coursewriter is a language developed for Inter- (b) R. P. Kropp, D. L. Hartford, H. W. Stoker, "Quar- national Business Machines Corporation CAI sys- terly Progress Report," Institute of Human Learn- tems; see (a) A. Maher, "ComputerBased Instruc- ing, Florida State University, Tallahasee, Florida, tion (CBI): Introduction to the IBM Project,"IBM October 1, 1965, December 31, 1965; (c) H. Mitzel Research Report RC1114, White Plains, NewYork, and K. H. Wodtke, "The Development and Presenta- 1964, and Ref. 1. For other languages see (b)D. L. tion of Four Different College Courses by Computer Bitzer, E. R. Lyman and J. A. Easley, Jr., "TheUses Teleprocessing," CAI Laboratory Interim Report, of Plato; A Computer-Controlled TeachingSystem," Pennsylvania State University,University Park, Report R-268, University of Illinois CoordinatedSci- Pennsylvania, 1965: (d) V. Bunderson, "The Texas ence Laboratory, Urbana,Illinois, 1965; (c) J. Mc- CAI Newsletter No. 1." The University of Texas, Aus- Carthy, P. W. Abrahams, D. J. Edwards, T. P.Hart, tin, Texas, February 15, 1966; (e) F. M. Tonge, and M. I. Levin, "LISP 1.5 ProgrammersManual," Computers and Universities, Irvine CAI System; A The Computation Center and ResearchLaboratory Workshop Conference, Newport Eeach, California, of Electror.fr:s, MassachusettsInstitute of Technol- November 8-12, 1965. ogy, Cambridge, Massachusetts,February, 1965; (d) J. G. Kemeny and T. E. Kurtz,"Basic," Dart- 3. For a description of existing CAI systems see, mouth College Computation Center, Hanover,New ft.example, (a)L. M. Stolurow and D. Davis, Hampshire, January 1, 1966; (e) S. Feingold,"A "Teaching Machines and Computer Based Sys- Flexible Language for ProgrammingComputer/ tems," Teaching Machines and Programmed Learn- Human Interaction," Systems DevelopmentCorpor- ing, II. (Robert Glaser, Ed.) Washington, D.C., Na- ation, Santa Monica, California, February28, 1966; tional Education Association of the UnitedStates, (f) L. M. Stolurow and H. T. Lippert,"Automatically 1965; (b) Q. Zinn, "Computer Assistance forIn- Translating Heuristically OrganizedRoutings: struction Automated Education Letter, 1, 4 (1965); AUTHOR I," Technical Memorandum No.21, Train- (c) R. J. Gentile, "First Generation ofComputer- ing Research Laboratory University ofIllinois, Ur- Assisted Instructional Systems: An Evaluation Re- bann, Illinois, February 10, 1966. view." Pennsylvania State University ComputerAs- 6.See, for example, J. A. Swets and W. Feurizig, UniversityPark, sistedInstructionLaboratory, "Computer Aided Instruction," Science,150, 572 Pennsylvania, 1965; (d) D. D. Bushnell, "Computcr- (1965). Based Teaching Machines," Journal of Educational Research, 55, 528 (1962); (e) D.L.Bitzer, P. 7. The first of this type of program was prepared Braunfield, and W. Lichtenberger, Plato II: A Multi- on the gorup I cations by R.S. Hirsch and B. Mon- ple-Student, Computer Controlled Automatic Teach- creiff (56th National Meeting of the AmericanInsti- ing Device," Programmer Learning andComputer- tute of Chemical Engineers, San Francisco,Calif., Based Instruction, (J. E. Coulson, Ed.) New York, May, 1965), followed by a program on the group John Wiley and Sons, Inc. 1962; (f) L. M.Stolurow, IV cations (J. J. Lagowski and C. E.Rodreguiz, "Socrates: System for Organizing Content to Review 152nd Meeting of the American ChemicalSociety, and Teach Educational Subjects," SeventeenthAn- New York, September, 1966).