Special Effects Projector
By
DAVID A. AGUILAR
Fiske Planetarium University of Colorado Boulder, Colorado
INTERNATIONAL PLANETARIUM SOCIETY Special Report No. 11 November, 1982 INTERN]\. TIONA L PLANET PRIUM SOCIETY
From: The Past President
To: International Planetarium Society's Membership
This is Special Publication No. ii, It is hoped that you will find this "Special Effects Booklet" to be of great ad vantage.
Mr. David Pguilar has over the past two years, tested and tried many of the special effects listed here. He needs to be congratulated on his fine work.
\Vhen a planetarium uses special devices to produce realistic astronomical phenomena, this enhances the visual concepts and therefore it increases learning. The planetarium profession has been growing in complexity each year, and along with it the programs also are more complex.
It is hoped that this booklet produced in a form that you may add to from time to time will be an important part of your planetarium library.
James .A. Hooks Past President International Planetarium Society I would like to thank the following people who so generously contributed their time and expertise to participate in this project, John Cotton for keeping me on track with those midnight phone calls from Texas, Don Hall for the postcards saying "Is it ready yet?", and especially Don McDonald for showing me how marvelous special effects can really be.
David A. Aguilar
CONTRIBUTORS
Mark Littmann - Hansen Planetarium Don Warren - S. F. City College Planetarium
Donald Mc Donald - Minolta Planetarium David Hurd - H.R. MacMillan Planetarium
Everett a. Carr - Herkimer Boces Planetarium Alan J. Friedman - Lawrence Hall of Science
Jan Paul Dabrowski Carl Dziedziech - Strasenburgh Planetarium
Jeff & Bob & Jeff Co. James R. Seebach - Charlotte Nature Museum
John Findlay - Centennial Planetarium William Schults Jr. - Cranbrook School Planetarium
Sig Wieser - Centennial Planetarium David Sanford - Shaker Heights Planetarium
Herbert J. Schwartz - Sargent Planetarium Kenneth Wilson - Morrison Planetarium
Thomas Hamilton- Wagner Planetarium D. Scott St Obbelaar - Marquette Sr. H.S. Planetarium
William L. Dutton - Edgerton Memorial Planetarium Michael F. Ryan - Earth Space Science Center Planetarium
Dwight E. Michael- Jay County H.S. Planetarium John C. Pogue - GPSID Planetarium
D. Scott Stobbelaar - Shiras Planetarium Russ Magg - Missouri Western State College
Marla Bowman - George Wallace Jr. Civic Center Ashley Godeaux - Fiske Planetarium
Larry Sessions - Noble Planetarium W.A. Deutschman - Bonisteel Planetarium
Don Garland - Richmond College Planetarium Don Hall - Strasenburgh Planetarium
Bob Lober - Chaffe College Planetarium Marvin Vann - Foothill College Planetarium
Jeanne Bishop - Westlake School Planetarium ,J.R. Andress - Warrensville Heights Planetarium
James R. Yankee - Enrico Fermi High School Planetarium Steven E. Smith - Arlington P.S. Planetarium
John Coolbaugh - Robert J. Novins Planetarium Bill Pounds - Arlington P.S. Planetarium
Don H. Anderson - Rochester, N. Y. Stephen R. Lattanzio - Orange Coast College Planetarium
Edward R. Grabowski - Michigan State University Charles Percival - School District 60 Planetarium
Charles L. Joseph - Abrams Planetarium ABLATION TRAIL
ABLATION TRAIL PROJECTOR, depending on its motor speed, can be used either as a passing rocket (1-2 RPM) or a bolide (5-10 RPM). Use a very heavy duty motor to move the projector or else you will get a very jerky motion across the sky_ A Hurst 600 inch ounce reversible motor works well.
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/ MOTOR, ASTEROID BELT
In the ASTEROID BELT IN MOTION projector, two cylinders, one within the other, rotate in the same direction at different rates of speed. This is accomplished using four gears, all of different sizes. The cylinders, which are made of metal to avoid heat warping or melting, were covered with aluminum foil which was perforated in a random pattern by placing it in a telephone book with a sheet of medium fine sandpaper and ham mering on the book until the desired pattern was attained, hole size, etc.. The aluminum foil was then cut to size and epoxied onto the hardware cloth cylinders. The inner cylinder's holes were made considerable larger by punching holes at random with a sharp pencil. See drawings for assembly data. The result is a shimmering band of star-like and larger objects moving in a continuous stream across the dome.
CARDBOAR.D SiR-IPS ( 6"FbXIED TO !-IOllSltV'"" TO HOL.D LENSES)
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To make an ATMOSPHERIUM for a small nine meter planetarium, two Bell and Howell Cube projectors are modified by substitut ing short focal length fisheye camera lenses (7.5mm-17mm) for the projection lens module. Inexpensive lenses can be found advertised in the back of such photographic magazines as Modern Photography and Photography.
Excellent all sky pictures are made from Eastman Kodak Ektachrome Infra Red film using a Wratten #12 yellow filter exposed at an ASA rating of 100. The film should have continuous refrigera tion prior to use to retain the color balance. The slides are made as lapsed time photographs at a picture taking rate of three pictures per hour. A thirteen hour and twenty minute day can be recorded on a total of eighty slides. They can be "re played" back at any desired rate using an automatic disolve unit.
Against bright skies, it may be necessary to use a neutral den sity filter to bring the exposure within the range of your shut ter speed and aperature available. If a friendly cloud is not handy to mask the sun, it will be necessary to create an arti ficial eclipse to prevent fogging the frame to insensibility. Kodak has phamphlets on the infra red film and on creating arti ficial eclipses for photographic purposes.
When ordering the projection lens, make sure you can adapt it to your own camera body. When used as a projection lens, the format of the slides used will have to be enlarged. Fortunately a simpl~ method exists for enlarging the image as required. At least two slide processing laboratories will make a 1.46X enlargement of a standard 35mm slide to an approximately 46mm diameter on the superslide format. Therefore, it is quite con venient to make the originals in a standard 35mm camera.
Figure 1 is a schematic of the optical path that allows vertical adjustment of the projector to a horizontal projection position. Figure 2 shows how the adjustment is accomplished and how the lens is mounted. SLIDE.
SELL ~ HOWELL CU8E PROJECTOR
~ LENS MOUNT
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LEN.S Mou~T DE.TA'L AURORA
AURORA PROJECTORS can be made by placing a motorized "ripple" wheel in front of a 100-150w slide projector with a 35mm slide of an aurora placed in the slide gate. Aurora pictures can be copied out of meteorolocical or astronomical books quite easily.
The ripple wheel is made from an 1/16"-1/8 IT thick disc of clear plexiglass with either Duco cement or Vaseline dabbed randomly on its surface.
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The CURTAIN AURORA is produced when light from a 605 lamp is reflected from a crumpled-foil surface onto the dome. The foil is mounted on a cardboard turntable attached to a 1 rpm motor. The moving reflecting surface causes the curtain to shimmer and change pattern. Color can be added by taping or pinning a skirt of multi-colored filters perpendicular to the disc's surface (Figure 1). With a 605 lamp, only pale yellows, blues and pinks are suitable. Darker colors may reduce the light output too much. If you desire brighter colors or want to use the projec tor in a large dome, replace the 605 lamp with a GE 1424 6v lamp.
The projector's enclosure can be made of sheet metal, wood, or black poster board. The poster board is durable provided it is not treated as a hands-on exhibit by the audience. It is also the simplest to build.
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Several variations of the projector are possible. Using two in tandem will produce a complex and brighter aurora. The mo tors may be of different rates to give longer periods between pattern repetition. The size, shape and placement of the exit opening on the enclosure can be varied to produce subtle changes in the aurora pattern. Once you build one, you will think of more variations.
The projector is mounted horizontally on the pedestal. The light from the exit slit falls slightly above the horizon cut off and extends 30 degrees vertically and 70 degrees horizon tally. When in operation, the projector is not visible to the audience since the slit is at least six inches above eye level. AURORA
This AURORA PROJECTOR utilizes a Pepsi bottle for the lens. When slowly rotated in front of three projected slits, a very realistic rayed arc aurora is produced.
The container box can either be constructed out of in plywood or corrugated cardboard. The slide is a 2" X 2" glass painted flat black, with three very fine lines scribed in the paint. Two green gels placed in the bottle, one around the inside, the other across the diameter, give the aurora colour. A three quarter inch black stripe painted vertically on the bottle causes the aurora to die out and reappear very realistically. Baffles may be required in front of the lens to shape the aurora.
/ SLIDE. WITH ~lITS
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The BIG BANG is a projector with a ragged-edge starburst type slide in it. A rapidly spinning gelled color wheel rotates in front of the slide. The lens is fitted with a hexidoscope tube (Edmund Scientific). The light path is folded by a prism or mirror and sent up an 8-inch piece of plastic tubing lined with wrinkled aluminized mylar or aluminum foil. A 7-inch focal length lens is cemented on top of this tube. Supported on a motorized rail above this assembly is a 9-inch focal length large diameter condenser lens smeared with Chapstick. This lens is arranged to drive from a point almost touching the 7- inch focal length condenser lens to 8 to 10 inches away from it. Driving the two lenses closer together zooms the effect. (The focal lengths are not critical: experiment with what is on hand.)
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The BLACK HOLE projector consists of a small opaque projector with a small crumpled ball of aluminum foil turning slowly on the extended shaft of a motor. The Black Hole is made by plac ing an occulting disc (a penny) in the light path of the pro jector between the foil ball and the lens. This projection, when properly light-shielded and projected out of focus through a blue or purple filter, beautifully simulates a Black Hole.
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MOTOR.. BLACK HOLE
The BLACK HOLE PROJECTOR consists of an illuminated rotating drum turning inside a gelled cover. The drum can be made from either a piece of 2" diameter clear plastic tubing or a baby food jar. Wrap half-inch masking tape in a spiral pattern around the drum and paint it flat black. Strip off the tape to reveal the clear spiral areas.
Mount the drum on a motor shaft inside the base. The outside cardboard base cover should be sprayed flat black before it is mounted over the drum. Experiment with different pieces of colored gel over the opening on the cover to achieve the desired effect.
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BLACK HOLE BINARY is created by having two sandwiched discs moving at slightly different speeds. Both discs, with thin (1/8") rims, are bearing mounted together (Figs. 2 & 4) and rim driven. Disc A has the Black Hole Kodalith artwork cemented onto one side of it. Both discs A and Bare 1/4" plexiglass. The large star on Disc A is dyed with red food coloring but the stellar gas loop remains clear.
Disc B has mask B, dyed purple, cemented to it emulsion side to the plastic. A small piece of coat hanger wire, flattened on one one end forms the Black Hole and joins the two discs together.
DISC 'A" ARTWORK.
1 RPM MOTOR.
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DISC. "B" AK'TWQ~K BOLIDE
THE BOLIDE PROJECTOR uses a fabricated cardboard drum with a kodalith bolide image rotated over a smaller drum containing the light source. The slot on the inner drum is covered with various pieces of colored gel taped to the outside of the slot.
The adjustable support base is an added extra that really makes positioning the projector an easy task. Make sure that you DO NOT epoxy glue both!" bolts into the stand support without the adjustable base matched up to it. This is the only way to get the two support axles in place.
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To create the illusion of a "Landing on the Moon", a BRUTE MOON ZOOM projector is made from two pieces of cardboard tubing that telescope fit together. Both are spray painted flat black in side and out. At the top of the outer tube, a 2"x2" transparen cy of the moon is glued on. A PR-12 lamp is secured by its socket inside the top of the inner tube. When the inner tube is pushed up, the lamp is kept from hitting the transparency by a masking tape stop ring secured to the outside of the smaller tube. The bottom tube is secured to the console and the pro jector is pointed towards the center of the dome. By pushing or pulling the small tube back and forth, the moon will zoom up and down almost filling the entire sky.
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The BURNING SUN EFFECT uses two slide projectors: one regular projector with a slide of the sun superimposed over an opaque projection of a rotating aluminum foil ball (motion upward). Set images to the horizon with the lower edge of the sun masked off.
A Sawyer's Rotodisk Projector (Edmund Scientific) can be used to make the opaque projector. The lens track portion is cut out and repositioned to the side.
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COVE ~O~.l2DN Lt~E:- CEPHEID VARIA LE
The CEPHEID VARIABLE projector uses a 100-500w slide projector with the film gate enlarged to accept an iris diaphram plate driven by a rod and cam shaft attached to a 1 rpm motor. Con nected also on the drive shaft of the motor is a rod that turns a color wheel in front of the projector lens. This color wheel is synchronized so that as the aperature opens up, the star turns from a white to a reddish-orange giant and then shrinks back again as it closes.
This projector can also be used to simulate a Nova or the Evo lution of a Star by replacing the color wheel with another one of different colors.
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The CHANGING SEASONS projector uses any slide projector with a special color wheel located behind a Kodalith nature scene. If the color wheel is placed in front of the slide, distortion will take place as the wheel rotates. The color wheel was painted with transparent paint (Edmund #71,607) and mounted on a i rpm motor. Seasonal changes are indicated by thes color changes.
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FRO~'-ED Li. SLUt: car W,",'lE CLOUDS
The CLOUD PROJECTOR is a very simple but effective special ef fect that is made from a six-inch petrie dish. The inside and outside of the dish is spray painted with flat black paint. The lid of the dish is smeared with black enamel to produce the clouds on the dome. The overlapping edge of the lid is also painted black. The lid is moved with a 1 rpm motor and the light source is a very common PR-12 lamp. The projector should be mounted near the center of the dome and two projectors work ing simultaneously give the best results.
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EPo)(Y GLUE. COLLIDING GALAXIES
The brute force COLLIDING GALAXIES projector is constructed around a set of four surplus spur gears, the larger the better. The galaxies are Kodalith transparencies taped to the lids of two three-pound coffee cans. The light source is a #605 lamp. The angle iron support bars are either soldered or epoxied to the bottom of the cans.
GEAR. COLOR ORGAN
In a COLOR ORGAN, musical notes trigger circuits which automatic ally light colored lamps. Each circuit responds to a different tone group. Bass notes trigger one channel; high notes trigger another. Music or sound is introduced into the color organ through a microphone or sound source (radio, tape recorder, phonograph). Once the sound enters the color organ, the highs, middles and lows are sorted out and used to modulate a colored light source or projector. The color organ can also be used to translate the human voice into light and color.
Edmund Scientific offers an inexpensive 3-channel Sound to Light control #42,309 that can handle up to 100w per channel. It is small enough to be placed either on top of the control console or mounted on a rack inside it.
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40 7.5 WATT XMAS L( 6f-\'rS COLORED RINGS
The COLORED RINGS effect supplies rings of slowly expanding shimmering colors. The color wheel is made by sandwiching large pieces of gel and black tape spirals between two discs of thin plexiglass. It is mounted in the slide plane of a projector and motorized to turn slowly. The tube is cardboard lined with heavy aluminized mylar. The angle at which the tube is mounted can be varied to change the size of the rings.
I /
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A unique COMET PROJECTOR can be quickly fabricated by bouncing a pinhole projection off a shiny ball bearing. The pinhole should be quite small and can be made by piercing a piece of aluminum foil with a sharp needle.
/ / / / / / / / / / /
RNHOLE - S L..l DE:. NOU~TEO AOM'I'JvM FOIl- IN A 100- 200w 5\..(\)£ t1?OJECToR. CONSTELLATIONS
A very simple and efficient CONSTELLATION PROJECTOR can be made as follows. Cut down a cardboard cylinderical container with a slip-on cover, that has a diameter of 3!" to a length of about 3!". An ice cream container does well. To the bottom secure a right angle of sheet metal about 1" square on each flange, by bolting it through to a miniature screw base socket. To it is bolted a duplicate angle using a wing nut. The bottom flange of this second sheet metal angle is screwed to a wood base.
A clear piece of acetate is tacked over the cover opening with masking tape and the lamp is turned on in the darkened star chamber. Turn the stars up full and point the projector towards the desired constellation. Dim the light as much as possible so that the stars can still be seen. With a red felt marker, sketch onto the clear acetate the rough outline of the constel lation while looking back and forth from the dome to the lid. The red lines should be visible projected onto the dome. Once you have the rough dimensions to fit the constellation, trans fer the drawing onto white paper, using black ink for the figure outline. Make a contact print using Kodalith Ortho film and tape this to the top of the projector. The size of the projec ted image can be slightly changed by moving the cover in or out on the cylinder.
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EPO'lY 6LU£' COSMIC AC
The COSMIC AC projector uses a 100-500w slide projector, a mo torized Bubble Wheel in the slide gate, and a Colored Clouds Lens. A connical light shield made out of black construction paper is placed over the Cloud Lens to reduce the amount of light spread to the dome. Different colored wheels produce a variety of energy fields.
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1 RPM MOTOR
COLORED C.LOuD L€I\J6 ~ (£.oPluAJl) #: 7~ 208)
-l. ~OO - 500 W CRASHING ASTEROID
The CRASHING ASTEROID consists of a moving bright dot which rapidly traverses the dome gaining speed as it travels. When it reaches the surface of the panorama, the dot disappears and an impact projector momentarily lights and fades. This gives the impression of a meteorite impact just over the horizon.
The dot projector can be made by mounting an aperture made in aluminum foil with a needle. It does not need to be circular. This is placed just in front of a 500w projector lamp. No con densers are needed. A projection lens of about 4" f.l. is used to form the image. If care is taken not to run the lamp for extended periods (more than ten seconds) no fan will be needed. The dot image is bounced off a moving mirror to make it travel across the dome.
The dot projector lamp is controlled by a triac of sufficient voltage and current rating to handle the lamp used. We used an 8 ampere 400 volt device in a plastic tab package. No heat sink is necessary because the lamp is only on for about 10 sec onds. The 15w horizon explosion lamp serves as a gate current limiting resistor for turning the triac on.
During the time the dot is traveling across the dome, the capac itor is charging up. R1 limits the charging current to avoid destruction of the diode. Its value will be determined by the diode used. In any case it must be small enough to allow the capacitor to charge fully in the traverse time. At impact, the 15w lamp is switched out of the triac gate circuit and across the capacitor. It glows brightly and fades, giving the impres sion of an explosion.
The impact flare is placed in the cove right under the spot on the panorama where the impact occurs. A bit of fussing with black tape, cardboard, scissors, and gels will give a nice ex plosion.
Two power cords are required. One is connected to 110 volts all the time. The other is switched 110 volts from the console. To operate the effect, this switch is thrown and held until impact takes place. The switch is then released and the pro jector resets itself using a microswitch. DISAPPEARING BINARY STAR
DISAPPEARING BINARY STAR illustrates a face-on view of a dou ble star system with one star appreciably more massive that the other. On cue, the more massive star disappears, leaving the small companion orbiting an invisible companion. As shown in Figure 1, two plastic discs are used. Disc #1 is grooved around the edge and mounted using two flanged ball bear ings and an a-ring motor-driven friction puck. At its center is an axle on which is mounted Disc #2. The mask for Disc #1 (Fig. 2) is simply two round aperatures, one smaller than the other, mounted and gelled to represent the two stars. Turning this disc causes the stars to orbit. Disc #2 mounts on the axle with some spring-loaded washers so that it will turn with Disc #1 when unrestrained. A small so lenoid is mounted to pull a wire braking arm against the edge of Disc #2, stopping its motion on cue. Its mask (Fig. 3) con sists of an opaque disc with a pie wedge 6ut out of it. By stopping the rotation of Disc #2, the inner star can be made to appear and disappear on cue. Once the desired effect has been achieved, release of the brake arm will cause the two discs to rotate back into the visible two star system.
PUCK
C€tJTER A'tLE DI~C *"1 WITH LJ\RC1E. 'D'~C!lPPE:~ftN6 ~'-A2 .2IV\c::1 SfV\A.~LE.(z' COMPAtJlON ~TAR.
DISC. ~ 2 WIT" O(,(.,Ut.:ffNC:1 MA'5K DISTANT LIGHTNING
The DISTANT LIGHTNING projector utilizes a 14" piece of clear plastic tubing capped at both ends with pieces of flat plastic. The tube should be sanded with #120 sandpaper until it is trans lucent. A 3/4" hole is then drilled in the middle of the tube so that a 110v 7 watt n~ght light and receptacle, wrapped in electrical tape, can be tightly inserted into the opening.
--- -- ~ --~- -~- ~~~ ~ --~ ~- ~~
EtE(.TR(CAl.. TAPE. PL.OC:r
Another type of DISTANT LIGHTNING projector can be made by using a baby food jar, masked off and gelled blue in place of the plas tic tubing.
8t\8V FODD Jf\R MA'5KED WtTH fl A.T BLAC,K pp.l~r
110v 7.5 vJ LAMP
Both projectors should be positioned in the cove area and con trolled by momentary contact switches back on the console. D UB -DUTY SLIP RING
There are occasional times when a planetarium operator-mechanic wishes a few more SLIP RINGS in some portion of his instrument. It is possible to double-up two circuits on one slip ring if both the circuits control only light bulbs.
Below is a typical control circuit for a bulb with variable brightness (such as a meredian projector).
110V t VARIABLE.. 3\1 CONTI
By using a new transformer and four diodes, two bulbs may be controlled separately; but only one slip ring is necessary.
~10V
NOTE: The direction of the diodes in the circuit is important and a transformer with twice the voltage of the original is required. This circuit has been used successfully on a Nova instrument to give separate controls for the sun, moon, and planet groups, where they were all on a single control origin ally. DOUBLE STAR
The DOUBLE STAR projector uses a 100-500w slide projector with a rotating star plate mounted inside the film gate. The cir cular star plate is cut from a piece of 1/4" clear plexiglass and covered with either a Kodalith mask or thin sheet of alum inum with one large red gelled aperature and one small blue gelled aperature glued to it with DUCO cement. The star plate is bearing mounted on an 1/8" aluminum plate and driven by a 1/2 rpm motor. Since neither star is centered on the mask, both will seem to rotate around a common center of gravity.
o o DUST STORM
A DUST PROJECTOR can be constructed by painting the outside of a clear plastic dome with patches or blobs of brown and orange transparent paint. The dome is supported on a large diameter ball bearing from a lazy susan. A timing motor and O-ring belt are arranged to drive the bearing. Inside is moun ted a 50-100w lamp.
12" DU\. TRAN6PA~f.N ,... 'DOM f,. (P.l»fUNO IIfP,I1f) 40-bOW ~ 1'DV LAMP LA'ZY $V6~N ~ 'Bf~~,N6 '-:.~~~~~~~$~~~~=~~~~.
A slightly more elaborate way to make a DUST PROJECTOR is to build an effect that consists of two contra-rotating cylinders (cardboard mailing tubes) covered with crumpled aluminum foil. Large pieces of black tape on the foil break up the reflection into cloud-like masses. The light source is a lOO-150w slide projector with a color wheel rotating in front of it. If you use a color wheel with blues and greens on it, you can achieve an underwater effect.
100 - 1'50 W PROJ EG TO\2.-
MOTORIZED COLOR WHEEL- ,?
Cl\\COBOARD TUBES ..,! 12" LoN'=?
~PM MOTOR. TH CHORD
The EARTH CHORD projector uses a clear plexiglass disc with a donut slide of the Earth glued to it. A wide-angle Buhl lens should be used to spread the image out as far as possible.
The projector should be placed on the horizon of the dome just above the cove.
If you substitute a round hole for the half-circle opening on the image plate, you will have an entire rotating planet instead of just a chord.
WaoE. AN 1!~_ 'Y10 RPM MOTOR.. *'FiI...M GLLJE:D TO Dl00c..-£MUL5(O)J 'Y4 If X '20 eeL-I TO 'PtCl .If (=;A RTH ~ HOR.D A~WO~K.- - STR~~e.N 6\1 RGH Pl.-A.N E-T ~R I U e'V\ 't..~B" CL€A.R. R/.\~TIL DI~GY EXPANDING/COLLA SING UNIVERSE The EXPANDING/COLLAPSING UNIVERSE projector utilizes a Fresnel lens covered with a black piece of construction paper contain ing several pencil-punched holes at random points. For domes up to thirty-feet in diameter, a PR-12 lamps will work quite well. For larger domes or brighter images, substi tute a GE 1424 lamp. Place the Fresnel lens about 13-inches above the light source so that a small area of concentrated light appears on the dome. By very slowly moving the Fresnel lens down toward the light source, one obtains the effect of galaxies rushing outward from a central point until the entire dome is covered with "galaxies". The effect of a collapsing universe can be obtained by slowly moving the Fresnel lens upward away from the light source. An alternative set up is to fix the lena to the open top of a box and fasten the small lamp to the top end of a moveable card board tube placed inside a fixed cardboard tube located in the center of the box and move the lamp toward and away from the lens. . BL~CK COtJ~"RlJCTlON ~AP€R PENCIL "PUN('HfD Wln.. \ 'f GAL AX IE. '5" FR.ESNEL 'Y41( PL'(WooD L.£N5 ovo CO~ROO~TeD (EDMVND CA~O~A.~D #74'70) ~ Su DING CAJ2DOOARD TUI3E A,sSE..M8LY EXTENDIBLE VIKING ARM To make an EXTENDIBLE SAMPLE ARM for the Viking Lander, the slide holder of a TMC projector is made to simultaneously hold two diffe~ent slides. Moving the slide-holder through the slide gate alternately reveals each slide. When used as a single slide projector, this dual slide-holder is usually re moved. The movement of this slide-holder in the gate is quite smooth, especially if lightly lubricated. With this slide gate and slide-holder, it was only necessary to motorize the slide-holder to move the desired slide across the projection field. The slide-holder can be easily motorized with various pieces of scrap hardware arranged to make a cam and push-rod to drive the slide holder. The longer the push-rod is made, the smoother the movement should be. We recommend that it be at least twice as long as the cam. The motor and slide-holder should be at the same level for smooth operation. The motor and slide-holder should be at the same level for smooth operation. The Viking Lander and its sample are were positioned on the panorama such that the sample arm appeared to telescope from behind the lander as its slide entered the slide gate. TM(' 1 RPM MOTOR / EVOLUTION OF A STAR An alternative method to using a color wheel to illustrate STELLAR EVOLUTION is to place stops of red gel inside the projector lens itself. Stops A and B are located just out of focus. The closed iris in focus gives a small white sun. As the iris opens, the image becomes larger and turns into a Red Giant. When setting up the throw of the eccentric cam shaft, make sure that it is not greater than the throw of the iris arm. MOTOl«ZE-D CAM :5J..\~F'- lRltS ..::(EI>MUNO #42,121) ~ \Rl~ R.E"'~'NIr-.1& ------SGREW- 150-300 W PROJECTOR- 1t<'5 ReTAINING SCREW (3) EXPANDING FIREBALL The EXPANDING FIREBALL projector uses a standard slide projec tor with a rotating color wheel focussed on a motorized mirror which bends the light beam us a 3!" diameter cardboard tube, two feet long. Line the tube with smooth aluminized mylar and cap it with a plexiglass disc gooped with DUCO glue and tiny colored gel fragments. Cp..fZD60l\~D ~ Vall )( 2411 I..(NE.D W rfH 5MOO-rt-' ~L\JMINIZISD MVa..A~ 1 RPM MbTO~ ~ GLOBULAR CLUSTER THE GLOBULAR CLUSTER projector uses a transparent acryllic dome painted an opaque flat black. Star holes ar~ drilled using the smallest drill bits possible. The base ring is for med out of a piece of thin cardboard 6" wide and approximately 24" in length. It is rolled and taped together at the edges to form a cylinder that is glued to the lip of the plastic dome. Five-minute epoxy or silicon glue works best. The base is made from a piece of llf plywood glued to the other end of the ring. There you have it--a chance to see what its like living on the outskirts of M-13. STAR. I-lOLf~ PLA. '51 \ c.. DOM E. {/3.[)MUND P. 11,710 (]V lib SO, 17'1) Ro\.. l,..e: 0 CAt --- "14" PL'(\!\lOCO D\SG ~ HYDROGEN/HELIUM ATOM The HYDROGEN/HELIUM ATOM projector uses a lOO-500w slide projec tor with an enlarged film gate to accomodate a rotating Koda lith mask, closely located next to a stationary Kodalith slide of the electron orbits of the atoms. The rotating slide disc is bearing mounted on the sides and driven by a friction puck. #A -l..lYDRD ,/s" c.Le~R Pl.E't(\Gt..A 8 EAt:( ( 1\lC::J MOll '" T \ ~C:t / PLATE. - Ye" ~L\JM'NUI'4\ ./ SL\Oe REv'EALER. ''50'" 500 W PRCJEC.1""Ot< IMAGE ROTATOR IMAGE ROTATION is accomplished by using a dove prism. To elim inate any light spill or possible double images, include a card board light baffle around the edges of the prism. Since image rotation speed is twice the rotation speed of the driving mo tor, anything rotated with a 10 rpm motor or faster will have a very fast spin rate. For a rotating satellite, a 1 rpm motor is recommended. £~T06RAA.. HC '5l, DE- ~oJEcrO R., LEI COPE The KALEIDOSCOPE consists of three pieces of glass about the size of microscope slides, two of which are aluminized with first-surface mirrors. They are assembled, along with the un coated glass, to form a triangular tube of glass with the re flecting surfaces facing inward. The edges are cemented with epoxy. Small objects are dropped into the box and strongly lit with a slide projector through the clear piece of glass. A projec tion lens placed above the box projects an enlarged image of the pattern on the dome. A second modification consists of cementing the kaleidoscope through a light framework of cardboard to the paper cone of an inexpensive speaker. Power from the tape deck or phonograph drives the speaker and jiggles colored fragments of plastic which are projected onto the dome. The small colored spheres known to confectioners as French's nonpareils, together with short lengths of colored plastic insulation stripped from cop per wire of No. 28 gauge, make effective fragments for opaque projection. Alternatively, the kaleidoscope is mounted on a transparent base, such as a two-inch cover glass of a slide mount. Mount the glass slide to a speaker cone with Silicone glue. Place a piece of polarizing material over the projection lens of the light source. Charge the kaleidoscope chamber with small crum pled wads of cellophane or other highly bifringent materials. Place another piece of polarizing material on top of the kal eidoscope projection lens. When the speaker is energized and the pclarizing sheets are adjusted, the details of the projec ted patterns change continuously in both form and color. WlOe. ANEJI.€• pROJEcroR I-e:NS ~ CLEAR GLA~ AL.UM\NIZED GLASS ~ 150-S-00vJ P"ROJE.GTOR. LENS ReMoveO • • KALEI DOSCOPE [DRY] A beautiful and fascinating DRY KALEIDOSCOPE projector can be made by inserting a motorized striped color wheel into the film gate of a lOO-500w slide projector with a Kaleidoscope Lens in place of the regular projector lens. By rotating the Kaleido scope lens, three different patterns and motions may be obtained. ~ 150 - SCOW WI-lfft,.. IMA<:"€. PROJe(';T"OR DIREGTION MOT'ON ( !' ~-w~y KAJ..eroOSCopE.. l.£N 5 ~iEDM()NO -- ~818) ~\OE. AN6t.E. 'PROJECTlOf.J l..-eNS ...... :::) CARD \3OARD 5~)( R~T'N6 00 CO PEA KE:.12.. F\ R~i '5\.)«. FACE f\/lIRRO(2... LASERS & GRAPHIC DESIGNS The LASER PROJECTION SYSTEM requires two mirrors that can be rotated electronically at high frequencies (~900 Hz) and a set of oscillators to drive them. If we want stationary pat terns or patterns that repeat themselves in time, the oscilla tors must be locked to some INTEGER multiple of a common refer ence frequency and maintain a constant phase relationship. Many two dimensional geometric forms such as stars and looped figures can be generated by superimposing four such sinusoidal waveforms with the correct frequency, amplitude and phase rela tionships. The method of maintaining these relationships will be discussed later. Given a device which can supply all the necessary frequencies, amplitudes and phase shifts, one is tempt ed to think that now all that is required is to twirl knobs in some almost random fashion creating many patterns. This is not the case. The control settings are delicate enough to re quire some degree of programming. The basic building block of our system is a phase-locked oscil lator which will lock on the first 10 harmonics of a given re ference frequency with zero phase error. (Fig. 1). We used a conventional edge triggered phase lock loop design utilizing CMOS logic for the divide by N and phase comparator. The VCO is the constant amplitude square wave section of an EXAR 2206. This unusual marriage of linear and digital circuitry works for power supply voltages between 10 and 15 volts. Calling the VCO frequency F, a frequency FIN is applied to the phase comparator which adjusts the VCO frequency until FIN is the same as the reference frequency. This gives a VCO frequen cy of N times the reference frequency. The 2206 simultaneously generates sine waves of the same frequency which can be ampli tude modulated with a control voltage. Phase shift can readily be introduced between two such oscilla tors with the circuit of Fig. 2. We generate a triangle wave with the desired reference frequency and apply it to a voltage comparator. The voltage at which the comparator switches de termines the phase of the reference pulse relative to the tri angle wave. Since the phase comparator is edge triggered, no complications arise from the variable duty cycle. No special circuit details are necessary other than those nor mally associated with high impedance CMOS logic. A block diag ram of the apparatus is shown in Fig. 3. Four phase-lock os cillators are mixed in pairs to generate X and Y scanner signals. Two control oscillators are available to modulate amplitudes. Let us now discuss some methods of obtaining graphic designs. Using just two oscillators, we start with a simple geometrical form like a straight line or an ellipse. The amplitude on each mirror is separately and rapidly changed up and down. This will create a beautiful abstract form. The persistance of the eye causes one to see an abstract form with many lines even though we are only drawing them one at a time. To create ano ther class of patterns we use all four oscillators. The X-axis oscillators are locked to 2 and 3 times the reference frequency and the Y-axis oscillators are locked to the same harmonics with a 90 0 phase difference. With some adjustment of the amplitudes a five pointed star will be created. Other patterns are obtained by changing the oscillators locked on 3F to some other harmonic. Of course there are other patterns which use different princi ples, but often a wealth of patterns can be obtained with only a slight variation of one or two controls. AMPliT uD E.. N Rf F 404b PH~'SE. LOW 220" N f DETEC.TOR 1- I- VCO PA~ (SI _~EF VOL"~~E. COM PARA.TOR. 40'S (SQvA~.E) ~N --- r-- P5 - 0 ,- PS =- PHASE. 5~ IFTE.~ ~ LOClCEO O~('ll .. 6a ~ o :: LATOR ~ ...... PS - 0 !- C"'VCO:: C.ON1ROL O'5C. (~e.o To AMPL.tTUDE.. MOD.) ReF - 6a NI~eR a !: AMp. MoO. INPUT" • - PS - 0 - ...... 0 y 6a --- P5 ,- 0 - 6, ~ [cvco LASER LUMIA To make a LASER LUMIA projector, construct a box with an in sert to hold the laser exactly (almost) perpendicular to twin spinning discs. One disc consists mainly of liquid cement, a JUPITERSCOPE, and some pre-popped bubbles (packing material). The other disc has that plus some diffraction gratings and a piece of lamp diffuser. One disc rotates at 2 RPH and the other at 6 RPH. This means that the pattern repeats itself every half hour. The biggest cost in this effect is the laser. Any RPM motor will do, but slower ones are more desireable because they are able to catch the more delicate and subtle patterns. The JUP ITERSCOPES are holographic diffraction disks that are available from Functional Products, Inc. in San Francisco. These holo graphic prisms are pocket-sized discs of clear flexible plastic that would make a neat sales shop item. 1" Df I).. ~O\"'E.. 2 RPH MVL.AR.. BETuJf~N MOTC)/ Two D'~S GRouNO GL.ASS SANOWtCHE.D B~TWE.f.N TWO 'OI!:£? HE.L1 UM- NEO t A hand held LIGHTNING PROJECTOR can be constructed using a cheap strobe (K-Mart) as the power source. Position and tape a Koda lith lightning slide over the diffusion lens of the ~trobe unit with black photographic tape so that no light can leak out around the slide. Mount a 4-6" focus PC or Achromat lens on the end of a cardboard tube and attach to the strobe unit over the Kodalith slide with tape or glue. You will have to experi ment first to obtain the proper focus before cutting the tube. Two hand-held projectors, pointed randomly around the dome, can provide quite a convincing lightning storm. K.. MA2r ~o~At. ~RAND ST~c>6e... J? \(CO~L.\TH UC':rI-\TNIN~ SLIDE (TIiPe oR- GLue. TO :srRost:j / Pr...A.N 0 - CON \lE.)( LE. N '5 4 -~" FOCAL.. L.E.~ ~T H /' L\(:H4ININ~ KCQ& - ~ LITH MASTE.&5 LIGHTNING The LIGHTNING PROJECTOR uses a rotating wheel made from various Kodalith slides of lightning bolts sandwiched between two pieces of 1/8" plexiglass. As the disc rotates, changing lighting bolts are flashed onto the dome. With the addition of the os cillating mirror assembly in Figure 2, the lightning bolts are randomly placed around the dome. 2. 12f'iV1 MOTOR fT t20-GC FL.A~HTL1BE. 20Cvl ~EC. r 2'1- '5" F. L . PROJEC.TloN L.EN'S CONDENSERS IORA:S'5 AN6LE.. ,-. (EPoxY ro M/~R()R.) WI2E SuPPoRrs RlH3Sf}<. GROMME.r FIC:I. 2 LIGHTNING Kodalith Master Graphics Use this Kodalith Master Graphics Sheet for the LIGHTNING images used in the lightning projector. Simply copy onto 35mm Koda lith Ortho film and mount onto a clear plastic disc. LIGHTNING POW R SUPPLY C1 01 fL~'5I-\TU6E.. ------41 ~+~---+----+------, nov AC + C-E~U 02 I t .---:-1...... , K 1 I I r ,I • iRI~ Cl 10mfd 400 wvolt electrolytic Dl, D2 1 ampere, 1000 volt c2 .5 mfd 400 volt mylar Rl, R2 ! watt, 2 megohm Tl Photoflash transformer C-ESU These capacitors are large value, high-voltage electro lytics. Be sure that their working voltage is at least 350 volts for 110 volt input. The necessary capacitance is compu ted with the formula E=!CV2 where E is energy in watt seconds, C is capacitance measured in microfarads, and V is volts mea sured in kilovolts. Make sure that the total capacitance and voltage used do not exceed the voltage and power capabilities of the flashtube used. Kl Relay is DPDT used to trigger strobe and disconnect charg ing current. CAUTION! I! THE CAPACITOR VOLTAGE CAN BE LETHAL!!! LOOP PROMINENCE The LOOP PROMINENCE projector gives the appearance of large a amounts of gas being exploded out from the sun and then fal ling back to the surface along a curved path. On the concave side of a 5" watch glass glue the 6" square of if! mirrors. Any type of epoxy glue will do. Trim off excess mirrors. Next, mount the watch glass on the motor by gluing a suction cup on the back of the watch glass with Silicone glue and then screw the cup onto the motor. The mirrored watch glass is used with a single-slide projector. Both are located in the cove just below an image of a portion of the solar disk. Use a slide with mottled yellow or red col ors, such as can be found in the Edmund Psychedelic Slide Sets. The slide projector is placed just far enough from the mirrors so that all the mirror surfaces are just covered by the pro jected light. ..I SUCTION 1 RPM MOTOR ___ --/ Morol' 6RACIC Er ~ LUNAR ECLIPSE The LUNAR ECLIPSE projector allows the moon to move in and out of the penumbra and umbra. The eclipse will occur wherever you wish, even if you have moved the star projector in latitu de or daily motion. The occulting disc is made out of two discs of clear plastic. The smaller disc is gelled red and mounted-un a larger, semi opaque disc used for the penumbral shadow. The occultor is mounted to the star projector in any convenient place with a thin flexible wire. To operate, place the moon where you want the eclipse to occur. Place the occulting device so that the moonlight will shine through it, producing the eclipse effect. Back the moon off and you are set. y~ "- ~" CLEAR. Pf..ACST( c.. - GEL.LEO RWIORANC:aE.. Wn<£ 50P'PoR.r p,"t-lO i=RoM M Ac~nJ E5 CONNECTED TO I...U1'lAR. PR()JE.c.rot2- PRcJE.C.Tof2 STAR. Mt~~2.... "'T A....,Y CoN"E~,e.~T POINr LUNAR ECLIPSE A simple LUNAR ECLIPSE projector is constructed out of a 100- 150w slide projector with an enlarged film gate modified to accomodate a rotating disc. The disc is made from 1/8" clear plexiglass with two pieces of orange gel scotch taped to it. Be careful to keep the tape on the outside edges of the colored gel so that it will not be picked up as part of the projected shadow image. If you have 'extra-steady' hands, thin crescent sections of light gray gel may be placed on either side of the orange umbral shadow to create a penumbral effect. ~"- 101( D/~. CLE.AR.. PL-E')(\(lt."ttSs DlSC. ~ OeANC::c E.. GEt... (Clef may ~Iso c.at"et~(''1 glv«2d ~to dt~ u~inc; doto cement.) MARS rtelescopic view] A TELESCOPIC VIEW OF MARS can be demonstrated by rotating a clear disc of glass or plexiglass in front of a slide project or containing a photograph of Mars. To create atmospheric dis turbances, lightly dab Vaseline onto the surface of the glass, adding or removing as needed. PLf.~(6Lt.\SS DISG (O~B6cD WITH "A~e.LltJe..) ~ 1 RPM MOTOR ~ 100-500W CSL.'OE. PRoJEC.TO~ PROJE.GTt O~ LENS CC\...02 SL.IDE OF MARS MULTI-COLOR DOME EFFECT The MULTI-COLOR DOME EFFECT can be used to illustrate the Big Bang Explosion, a nebula, or a planetary atmosphere. For best sky coverage, use two projectors positioned in the cove area 180 0 apart. '3" 01A. M)'LAR, ~C.O"ERED ~~(",{NDE.R- CeJ..-DRED GEL :;'TF<-tP5 MULTIPLE IMAGES MULTI-IMAGE effects can be used for passage through Black Holes, Time Warps, and various other Light Show effects by using one of the many different Mul ti-Image lenses availa,ble from any large photographic store. The lens can be attached to the front of the projector lens with a piece of tape or can be motorized to turn in front of the projector lens to bring a rotating motion into effect. o TIFFEN Multiple-Image lenses 3P 3R 5P 5R 6L 6D NEBULA The FULL SKY NEBULA uses a 100-150w slide projector with a multi-colored gelled slide in the film gate. The motorized wheel is made from either a disc of i-inch plywood or corru gated cardboard. Crumple the aluminum foil first before glu ing it down on the disc. The lens of the projector should be adjusted for best coverage or can be completely removed altogether. The light pattern should scatter to all parts of the dome. ScATTERE.D L.16H'- CAROBO~2.P DISC. c.ov~eo W'TH CROMPle.D ~L\JM\t\h.JM Fou ... 1- '2.. 'RPM MOTO~ NOVA A NOVA may be quickly made by placing a #605 lamp through an enlarged hole in the dome. The brightness can be varied by a power supply located near the console. For a SUPERNOVA, project a Crab Nebula slide over the lamp. As you zoom up the nebula, increase brightness and turn down the bulb to illustrate the explosion of the star. These bulbs are so small that they go unnoticed and several can be placed at various locations around the dome. One dip ped in yellow transparent paint works quite well as the sun seen from Pluto. A small but efficient four lamp CONTROL BOX can be made out of i" plywood and five SPST switches. Attach the box to the side of the console and run a short power line from the pointer jones plug on the console to the switches inside the box. Add another female jones plug on one end of the control box for your pointer to plug back in to. The first SPST switch controls the pointer. By flipping the pointer off and one of the other switches on, the pot on the main control console can be used to vary the brightness of the other #605 lamps around the dome. ft)Wf£ PlJJ6 I N<6E.IZTED '~TO OL.D po,~\~ RE!.E?iA<: L.E- OtJ CONSOlE. ; SOLAR WIND ST EA The SOLAR WIND projector is placed near the projected image of the burning sun--tilted at a high angle along the dome so that streams spread away from the sun. Twisted, fluted clear plas tic rods are available at most plastic supply houses. A Saw yer's Rotodisk projector is used for the basic system and hous ing. The projector's lens should be replaced with a cheap wide-angle single lens or an Erfle short focus eyepiece. The color"wheel is brushed with light blue, green, purple, etc. transparent paints. The solar wind streams are taped or painted onto the square piece of plexiglass. 35'0- 5COW 5L \OE PKOJEGTOR. LJqHT SY~TEM WIDe AN6L(:, LENS (OLO E.flf"LE. 0'(' GIW&LE. SHO(ll FOC\JS \..€.~S 'ROTA.TlNc:r \5 RPM I TWI~re.D t= L.VTEO CLE.~rG PL"bTIG RW co(,o~ WHt£ l ( SLuE - 6Rf£tJ - Pu~PL€ - erG.) SOL.AR. Wl....,D ST£.€AM M~&~ (PA\NT or T~PE C)rJro Cc.,E,AR. Pt.E)(( G\...A.SS ) UTILITY SLID ROJ CTOR The UTILITY SLIDE PROJECTOR is made out of a simple wood or sheet metal housing and provides an inexpensive method of ob taining a set of auxilIary projectors. With the addition of the removeable slide holder in Figure 2, the projector gate becomes accessible for color wheels, image rotators, and other special effects that require the modification of a standard projector. The top metal ventilator may be found in some building supply stores. If you wnat to boost the lamp to 150w, be sure and include some sort of fan so you won't end up cook ing your slides. S"e'ET METAl- VENTILATOR ("I/ARbWAIlE. :srOR..E) METAL. l..lE7l4-T H~f.. ZODIACAL LIGHT J3~5E at'\d TRAt-JSfORMER