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Ira Sprague Bowen Papers, 1940-1973
http://oac.cdlib.org/findaid/ark:/13030/tf2p300278 No online items Inventory of the Ira Sprague Bowen Papers, 1940-1973 Processed by Ronald S. Brashear; machine-readable finding aid created by Gabriela A. Montoya Manuscripts Department The Huntington Library 1151 Oxford Road San Marino, California 91108 Phone: (626) 405-2203 Fax: (626) 449-5720 Email: [email protected] URL: http://www.huntington.org/huntingtonlibrary.aspx?id=554 © 1998 The Huntington Library. All rights reserved. Observatories of the Carnegie Institution of Washington Collection Inventory of the Ira Sprague 1 Bowen Papers, 1940-1973 Observatories of the Carnegie Institution of Washington Collection Inventory of the Ira Sprague Bowen Paper, 1940-1973 The Huntington Library San Marino, California Contact Information Manuscripts Department The Huntington Library 1151 Oxford Road San Marino, California 91108 Phone: (626) 405-2203 Fax: (626) 449-5720 Email: [email protected] URL: http://www.huntington.org/huntingtonlibrary.aspx?id=554 Processed by: Ronald S. Brashear Encoded by: Gabriela A. Montoya © 1998 The Huntington Library. All rights reserved. Descriptive Summary Title: Ira Sprague Bowen Papers, Date (inclusive): 1940-1973 Creator: Bowen, Ira Sprague Extent: Approximately 29,000 pieces in 88 boxes Repository: The Huntington Library San Marino, California 91108 Language: English. Provenance Placed on permanent deposit in the Huntington Library by the Observatories of the Carnegie Institution of Washington Collection. This was done in 1989 as part of a letter of agreement (dated November 5, 1987) between the Huntington and the Carnegie Observatories. The papers have yet to be officially accessioned. Cataloging of the papers was completed in 1989 prior to their transfer to the Huntington. -
Instruction Manual
INSTRUCTION MANUAL Table of Contents 1. Setting up the EQM-35 mount .................................................. 1 1.1 Setting Up the tripod ................................................................................... 1 1.2 Attaching the mount ..................................................................................... 1 1.3 Attaching the accessory tray ....................................................................... 1 1.4 Installing the Counterweights ..................................................................... 2 1.5 Installing slow-motion control handles ..................................................... 2 1.6 Installing electrical components ................................................................. 3 1.7 Installing optional accessories to turn the EQM-35 PRO into the EQM-35 PRO light photographic traveling version ............................................ 4 1.8 Installing optional accessories to turn the EQM-35 PRO into the EQM-35 PRO super light photographic traveling version ................................ 5 2. Moving and balancing the EQM-35 mount ............................. 6 2.1 Balancing the mount: ................................................................................... 6 2.2 Orienting the mount before starting (polar aligning): ............................. 7 2.3 Pointing the telescope with the EQM-35 mount ...................................... 8 3. Use of the polar scope (precise polar aligning) .................. 12 3.1. Aligning procedure for the northern hemisphere: -
As the Dome of Twilight Sinks Below The
As the dome of twilight sinks below the horizon, a mechanical corps de ballet starts a slow-motion pirouette with each dancer keeping the unblinking eye of a telescope locked on a single spot in the heavens. Shutters open and ancient photons, ending a journey that may have started before the earth was born, collide with sensors that store an electron to mark that photon's arrival. With the dance in motion the directors sit back to watch the show; another imaging session has begun... Image by Marcus Stevens A Full and Proper Kit An introduction to the gear of astro-photography The young recruit is silly – 'e thinks o' suicide; 'E's lost his gutter-devil; 'e 'asn't got 'is pride; But day by day they kicks him, which 'elps 'im on a bit, Till 'e finds 'isself one mornin' with a full an' proper kit. Rudyard Kipling Like the young recruit in Kipling's poem 'The 'Eathen', a deep-sky imaging beginner starts with little in the way of equipment or skill. With 'older' imagers urging him onward, providing him with the benefit of the mistakes that they had made during their journey and allowing him access to the equipment they've built or collected, the newcomer gains the 'equipment' he needs, be it gear or skills, to excel at the art. At that time he has acquired a 'full and proper kit' and ceases to be a recruit. This paper is a discussion of hardware, software, methods and actions that a newcomer might find useful. It is not meant to be an in-depth discussion of all forms of astro-photography; that would take many books and more knowledge than I have available. -
The Celestron Edgehd a Flexible Imaging Platform at an Affordable Price
A FLEXIBLE IMAGING PLATFORM AT AN AFFORDABLE PRICE Superior flat-field, coma-free imaging by the Celestron Engineering Team Ver. 04-2013, For release in April 2013. The Celestron EdgeHD A Flexible Imaging Platform at an Affordable Price By the Celestron Engineering Team ABSTRACT: The Celestron EdgeHD is an advanced, flat-field, aplanatic A skilled optician in a well-equipped optical shop can reliably series of telescopes designed for visual observation and imaging produce near-perfect spherical surfaces. Furthermore, by with astronomical CCD cameras and full-frame digital SLR comparing an optical surface against a matchplate—a precision cameras. This paper describes the development goals and reference surface—departures in both the radius and sphericity design decisions behind EdgeHD technology and their practical can be quickly assessed. realization in 8-, 9.25-, 11-, and 14-inch apertures. We include In forty years of manufacturing its classic Schmidt-Cassegrain cross-sections of the EdgeHD series, a table with visual and telescope, Celestron had fully mastered the art of making imaging specifications, and comparative spot diagrams for large numbers of essentially perfect spherical primary and the EdgeHD and competing “coma-free” Schmidt-Cassegrain secondary mirrors. designs. We also outline the construction and testing process for EdgeHD telescopes and provide instructions for placing sensors In addition, Celestron’s strengths included the production of at the optimum back-focus distance for astroimaging. Schmidt corrector plates. In the early 1970s, Tom Johnson, Celestron’s founder, perfected the necessary techniques. Before Johnson, corrector plates like that on the 48-inch 1. INTRODUCTION Schmidt camera on Palomar Mountain required many long The classic Schmidt-Cassegrain telescope (SCT) manufactured hours of skilled work by master opticians. -
A Guide to Smartphone Astrophotography National Aeronautics and Space Administration
National Aeronautics and Space Administration A Guide to Smartphone Astrophotography National Aeronautics and Space Administration A Guide to Smartphone Astrophotography A Guide to Smartphone Astrophotography Dr. Sten Odenwald NASA Space Science Education Consortium Goddard Space Flight Center Greenbelt, Maryland Cover designs and editing by Abbey Interrante Cover illustrations Front: Aurora (Elizabeth Macdonald), moon (Spencer Collins), star trails (Donald Noor), Orion nebula (Christian Harris), solar eclipse (Christopher Jones), Milky Way (Shun-Chia Yang), satellite streaks (Stanislav Kaniansky),sunspot (Michael Seeboerger-Weichselbaum),sun dogs (Billy Heather). Back: Milky Way (Gabriel Clark) Two front cover designs are provided with this book. To conserve toner, begin document printing with the second cover. This product is supported by NASA under cooperative agreement number NNH15ZDA004C. [1] Table of Contents Introduction.................................................................................................................................................... 5 How to use this book ..................................................................................................................................... 9 1.0 Light Pollution ....................................................................................................................................... 12 2.0 Cameras ................................................................................................................................................ -
To Photographing the Planets, Stars, Nebulae, & Galaxies
Astrophotography Primer Your FREE Guide to photographing the planets, stars, nebulae, & galaxies. eeBook.inddBook.indd 1 33/30/11/30/11 33:01:01 PPMM Astrophotography Primer Akira Fujii Everyone loves to look at pictures of the universe beyond our planet — Astronomy Picture of the Day (apod.nasa.gov) is one of the most popular websites ever. And many people have probably wondered what it would take to capture photos like that with their own cameras. The good news is that astrophotography can be incredibly easy and inexpensive. Even point-and- shoot cameras and cell phones can capture breathtaking skyscapes, as long as you pick appropriate subjects. On the other hand, astrophotography can also be incredibly demanding. Close-ups of tiny, faint nebulae, and galaxies require expensive equipment and lots of time, patience, and skill. Between those extremes, there’s a huge amount that you can do with a digital SLR or a simple webcam. The key to astrophotography is to have realistic expectations, and to pick subjects that are appropriate to your equipment — and vice versa. To help you do that, we’ve collected four articles from the 2010 issue of SkyWatch, Sky & Telescope’s annual magazine. Every issue of SkyWatch includes a how-to guide to astrophotography and visual observing as well as a summary of the year’s best astronomical events. You can order the latest issue at SkyandTelescope.com/skywatch. In the last analysis, astrophotography is an art form. It requires the same skills as regular photography: visualization, planning, framing, experimentation, and a bit of luck. -
2014 Stellafane Convention
2014 Stellafane Convention The 79th Convention of Amateur Telescope Makers on Breezy Hill in Springfield, Vermont 43° 16’ 41” North Latitude, 72° 31’ 10” West Longitude Thursday, July 24 to Sunday, July 27, 2014 “For it is true that astronomy, from a popular standpoint, is handicapped THE STELLAFANE CLUBHOUSE by the inability of the average workman to own an expensive astronomical The clubhouse was designed by Porter and constructed by the members. The telescope. It is also true that if an amateur starts out to build a telescope just pink color may simply have been that of donated paint, but it has been hal- for fun, he will find before his labors are over that he has become seriously lowed by long tradition. Although interested in the wonderful mechanism of our universe. And finally there is it’s now a tight fit with today’s larg- understandably the stimulus of being able to unlock the mysteries of er membership roster, the Spring- the heavens by a tool fashioned by one’s own hand.” field Telescope Makers still hold —Russell W. Porter, Founder of Stellafane, March, 1923 meetings at Stellafane. The origi- nal site, including the clubhouse SOME STELLAFANE HISTORY and the Porter Turret Telescope, In 1920, when a decent astronomical telescope was far beyond the average was designated a National Historic worker’s means, Russell W. Porter offered to help a group of Springfield ma- Landmark in 1989. Photo is from chine tool factory workers build their own. Together, they ground, polished, 1930s. and figured mirrors, completed their telescopes, and began using them, soon THE PORTER TURRET TELESCOPE becoming thoroughly captivated by amateur astronomy. -
Orion Atlas EQ-G Equatorial Mount Instruction Manual
INSTRUCTION MANUAL Francais ➊Pour obtenir le manuel d'utilisation complet, ™ veuillez vous rendre sur le site Web OrionTe- Orion Atlas EQ-G lescopes.eu/fr et saisir la référence du produit dans la barre de recherche. Equatorial GoTo Mount ➋Cliquez ensuite sur le lien du manuel d’utilisation du produit sur la page de descrip- tion du produit. #9996 Deutsche ➊Wenn Sie das vollständige Handbuch ein- sehen möchten, wechseln Sie zu OrionTelescopes.de, und geben Sie in der Suchleiste die Artikelnummer der Orion-Kamera ein. ➋Klicken Sie anschließend auf der Seite mit den Produktdetails auf den Link des entspre- chenden Produkthandbuches. Español ➊Para ver el manual completo, visite OrionTelescopes.eu y escriba el número de artículo del producto en la barra de búsqueda. ➋A continuación, haga clic en el enlace al manual del producto de la página de detalle del producto. Italiano ➊ Per accedere al manuale completo, visitare il sito Web OrionTelescopes.eu. Immettere the product item number nella barra di ricerca ➋ Fare quindi clic sul collegamento al manuale del prodotto nella pagina delle informazioni sul prodotto. Corporate Offices: 89 Hangar Way, Watsonville CA 95076 - USA Toll Free USA & Canada: (800) 447-1001 International: +1(831) 763-7000 Customer Support: [email protected] AN EMPLOYEE-OWNED COMPANY Copyright © 2020 Orion Telescopes & Binoculars. All Rights Reserved. No part of this product instruction or any of its contents may be reproduced, copied, modified or adapted, without the prior written consent of Orion Telescopes & Binoculars. IN 279 Rev. F 09/20 Saddle Dovetail mounting bar Saddle clamp knobs Declination setting circle Dec clutch lever Front opening Drive panel Right Ascension setting circle Counter weight shaft lock lever R. -
Historyofthetelescope
HISTORY OF THE TELESCOPE Pedro Ré http://pedroreastrophotography.com/ Contents Joseph von Fraunhofer (1787 - 1826) and the Great Dorpat refractor .................................................. 3 Alvan Clark (1804-1887), George Bassett Clark (1827-1891) and Alvan Graham Clark (1832-1897): American makers of telescope optics. .................................................................................................. 13 William Parsons (1800-1867) e o Leviatã de Parsonstown (in Portuguese) ......................................... 21 O Telescópio de Craig (1852) (in Portuguese) ...................................................................................... 29 The 25-inch Newall Refractor ............................................................................................................... 37 The Kew Photoheliograph ..................................................................................................................... 43 O Grande Telescópio de Melbourne (in Portuguese) ........................................................................... 51 O Grande Refractor da Exposição de Paris (1900) (in Portuguese) ...................................................... 61 William Lassell’s (1799-1880) Telescopes and the discovery of Triton ................................................ 71 James Nasmyth’s (1808-1890) telescopes ............................................................................................ 77 The 36-inch Crosley Reflector .............................................................................................................. -
Ioptron's New ZEQ25GT Mount
Test Report S & T Test Report For more information about Sky & Telescope magazine or to subscribe visit SkyandTelescope.com or phone --. Dennis di Cicco iOptron’s New ZEQ25GT Mount There’s more to this equatorial Go To mount than just a radical new design. ZEQGT U.S. price: from (as tested: , including tripod, polar-alignment scope, carrying case, and tripod bag) iOptron F Gill St., Woburn, MA ; ioptron.com; -- Tipping the scales at only ½ pounds ( kg) without the counterweight shaft, the ZEQGT is compact and very portable. The pivoting counterweight shaft clears the tripod legs when the mount is set for low latitudes all the way to the equator. ALL PHOTOS BY THE AUTHOR UNLESS OTHERWISE CREDITED ©2014 New Track Media, LLC. Reprinted with permission from Sky & Telescope. SKY & TELESCOPE • March 2014 S&T Test Report S if I’m wrong, but I can’t recall a company ever off ering a wider variety of telescope mounts than iOptron currently does. From small and midweight alt-azimuth designs to a range of German equatorials, the company has the biggest selec- tion of Go To mounts available today. Although iOptron’s lineup stops short of the massive “observatory” equatorials used by elite astrophotographers, its off erings fully cover the workhorse needs of amateur astronomy. I’ve spent decades using portable equipment everywhere from my driveway to the Australian Outback, and there’s never been SEAN WALKER SEAN an occasion when I wouldn’t have been well served by one S&T: of the mounts currently available from iOptron. Above: Mentioned in the text, iOptron’s CEM (seen here at its One of the company’s newest Go To equatorials is the unveiling last November at the Arizona Science & Astronomy Expo) ZEQGT. -
A Barlow Lens Increases the Focal Length of a Telescope Without Increasing the Physical Length Correspondingly
A Barlow lens increases the focal length of a telescope without increasing the physical length correspondingly. It is a useful way of obtaining higher magnifications without using very short focal length eyepieces. Barlow lenses used to be sold with a specified focal length. The lens was fitted into a cell, within a tube that could be slid into the drawtube. The increase in the focal length could be varied by altering the separation between the Barlow lens and eyepiece. Now, because telescope focusers tend not to have drawtubes, they are sold with a specified, and usually fixed, amplification. Spacer tubes may be supplied to change the amplification. The Barlow lens is negative, and needs to be achromatized, to maintain the spherical and chromatic correction of the telescope objective. The change in the focal length is given by the universal lens formula: 1 1 1 = − f u v where f is the lens focal length v is the object distance u is the image distance € Defining Barlow lens parameters as the negative focal length B, distance inside the prime focus D, and separation between Barlow lens and effective focus S, 1 1 1 = − B S D € and when the negative focal length B is known, can be rearranged in terms of D: SB D = S + B S Image amplification is given by A = D € from which S = B(A −1) The increase in telescope€ tube length is S − D. The Barlow lens cannot be€ placed inside the prime focus by more than its focal length. If placed at its focal length inside prime focus the effective focus becomes infinite. -
User Manual Nomenclature
GERMAN TYPE EQUATORIAL MOUNT (FM 51/52 - FM 100/102 - FM150) USER MANUAL NOMENCLATURE WORM DRIVE TIGHTENING SCREW DECLINATION AXIS FIXING CLUTCH DECLINATION AXIS MANUAL KNOB DECLINATION AXIS CONTROL PLUG POLAR SCOPE PEEP PLATFORM HOLE POLAR AXIS CONTROL PLUG ALTITUDE MOUNTING SCREW AZIMUT SETTING SCREW POLAR AXIS MANUAL KNOB AZIMUT FIXING SCREW POLAR AXIS FIXING CLUTCH HOW TO SET UP? Installing telescopes and counterweights. Balancing the system. After placing the mount on the column, the optics have to be put on the platform. Make sure that the weight of the telscope is constantly and gradually increased on the mount. A good idea here could be placing a counterweight on the counterweight axis, as near as possible to the root of the axis and then mounting the telescope. When mounting several telescopes the above described procedure applies with one counterweight followed by one telescope and so on. After that first try balancing the polar axis by moving the counterweight. Use additional counterweights if necessary. The next step is balancing the declination axis by adjusting the tubering (not included). The excentricity of the counterweight previously installed can enhance this procedure. As the boreholes on the counterweights are not symmetrical, by rotating the counterweight around the axis one can finetune the balance of the declination axis. Continue with this procedure until both axes of the system are balanced. Alignment 1. ALIGNMENT USING A POLAR TELESCOPE Alignment is most easily done with the help of a polar telescope. Insert the polar telescope in the polar telescope slot of the mount (a connecting adapter might be needed due to possible incompatibility with some polar telescopes).