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20-536: Questar may refer to: Questar Corporation , telescope manufacturer Questar Corporation (gas company) , natural gas-focused energy company Questar, cartoon character leader of the Valorians in Dino-riders Questar Science Fiction , publisher of science fiction Bull Questar , Honeywell-Bull brand of mainframe terminals Topics referred to by

40-458: A "Gregory-Maksutov" or a "Spot-Maksutov". Gregory's article included detailed optical specifications as well as shop techniques and testing algorithms. Many more articles were published by Gregory and others on his design in the "Gleanings for ATMs" column in Sky & Telescope , culminating in the 39-page pamphlet Gleanings Bulletin C . Gregory went on to design a 22-inch f/3.7 Maksutov telescope for

60-464: A hole on the back of the Control Box. A knob for focus and another to switch in and out a magnification-doubling Barlow lens rounded out the controls. The cast-aluminum double-fork arm mount was designed with a built-in clock drive and became equatorial by adding the collapsible legs included. It also included a star chart engraved in white on a blue aluminum sleeve (this doubles as a dewcap), around

80-450: A small aluminized spot on the inner surface of the corrector lens. Not only was Gregory's design simpler than the classical Maksutov design; it also had the advantage of fixing the alignment of the secondary, making the telescope more robust, and eliminating the need for a secondary support that would otherwise cause diffraction spikes in the image. Most Maksutov telescopes manufactured today are of this type, which has come to be called either

100-693: A telescope manufactured by the company. Questar produces telescopes for consumer, military, police, security, aerospace, and industrial applications. Products sold by Questar include 3.5” (89 mm) and 7” (178 mm) aperture Maksutov Cassegrain astronomical/terrestrial telescopes for the consumer market. For a while they also offered 12-inch (300 mm)-aperture optical-tube assemblies. They are used in astronomy, nature study, radar calibration/ boresighting /tracking rocket launches, surveillance, and as long-distance microscopes. Questar does not produce their own optics. The earliest Questars used optics produced in part by Cave Optical, but for most of their history

120-532: Is different from Wikidata All article disambiguation pages All disambiguation pages Questar Corporation Questar was founded in 1950 by Lawrence Braymer, who set up Questar to develop and market Maksutov telescopes and other optical devices for the consumer, industrial, and government customers. The Questar Standard telescope has been in production since 1954. Questars have been associated with many well-known scientists and other personalities; for example, in 1959, Wernher Von Braun purchased

140-641: The Riverside Telescope Makers Conference . He was also active in politics, serving in several political action groups that lobbied for tort reform. John Gregory died on November 14, 2009, following an automobile accident. The car his wife Carolyn was driving in Lakeway, Texas , was struck by a pickup truck around 8:20 am. He and Carolyn were flown to University Medical Center Brackenridge in Austin . John died later that day from injuries sustained in

160-520: The Stamford Museum and Nature Center in Connecticut; this telescope is still the largest Maksutov in the U.S. In 1980 he donated an 8.2-inch f/16 Maksutov-Cassegrain that he had constructed to his alma mater, Case Western Reserve; he named it the "Nassau Memorial Telescope" after his former teacher there, astronomer J. J. Nassau . At the 2006 Riverside Telescope Makers Conference, Gregory delivered

180-640: The Case Institute of Technology (now Case Western Reserve University ). In the 1950s he began his career working for Perkin-Elmer Corporation in Norwalk, Connecticut . In the 1960s he worked for Barnes Engineering Company in Stamford, Connecticut, where he designed and tested lenses used in the infrared and ultraviolet. In 1974 he became chief engineer for the University of Texas McDonald Observatory . In 1978 he left

200-473: The Maksutov corrector plate, creating a compact folded light path (this design is sometimes called a "Spot-Maksutov"). Braymer designed a built-in “Control Box” that allowed the user, looking through the main eyepiece, to switch between the main telescope and a coaxial finderscope via moving a diagonal out of the way with a flick of a knob. This also allowed a camera or other device to access the focal plane through

220-649: The Questar 3.5" with the integrated Control Box, the Questar Seven, with a nominal 2400mm focal length, has twice the aperture and four times the light gathering power of the 3.5. The form-factor is similar to the 3.5 Duplex model as the barrel is separate but attaches to the base of the clock drive assembly. After over fifty years in production, the Seven remains rare. Using a sequential serial numbering system, approximately one thousand units have built since production began. The Seven

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240-499: The Robert Fulton Goff Invitational Lecture on Optics and Optical Design, entitled "My 60 Years of Astro-Optics". John Gregory had two sons, Rick and Randy, with his first wife Barbara, lost his second wife Marion to brain cancer, and was married in 1998 to Carolyn. He was an accomplished pianist, jewelry maker, and pilot. He was a frequent attendee at meetings of amateur astronomers, including Stellafane and

260-457: The barrel which contained a moon map. To avoid a conflict with a design patent held by John Gregory licensed to PerkinElmer , Braymer put the secondary spot on the outer (R1) surface of the corrector lens. In the mid-1960s the patent issue was settled, and Questar’s Maksutov-Cassegrains after that time use the Gregory design with the aluminized spot on the inside of the corrector (R2). The design

280-411: The field of amateur astronomy where resolution and light-gathering power are the primary requirements for a telescope, the Questar 3-1/2's comparatively small aperture has led the instrument to be criticized by some as too small and too expensive. A 7-inch (180 mm) model was introduced in 1967 for amateur and professional astronomers, hobbyists, industry and government. A scaled-up version of

300-572: The observatory and opened Gregory Optics, an optical and telescope equipment consulting, design, and fabricating firm. In 1957, Gregory published an article in Sky & Telescope magazine entitled "A Cassegrainian-Maksutov Telescope Design for the Amateur". In it, Gregory showed how to construct a version of the Maksutov catadioptric telescope in which all optical surfaces are spherical, and which has as secondary

320-431: The optics were produced by Cumberland Optical. In development since 1946, the Questar 3-1/2 has been the company's most notable product. Braymer’s basic concept for the telescope was one of portability, compactness, and ease of use. He used a catadioptric Maksutov design, named after its inventor Dmitry Maksutov , for the optical tube assembly. Braymer used a modified Cassegrain design that added an aluminized spot to

340-410: The same term [REDACTED] This disambiguation page lists articles associated with the title Questar . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Questar&oldid=734266104 " Category : Disambiguation pages Hidden categories: Short description

360-447: The telescope's mechanical and optical design, educational value for children, ease of use, and adaptations as a spotting scope and telephoto lens . The Questar of the 1950s and early 1960s had a proprietary screw in eyepiece design and offered little capacity to employ third-party accessories. Later models accept standard slide-in 1.25" eyepieces and other accessories. The Questar 3.5” has been sold in variants including: For use in

380-526: Was also very expensive for its intended market and has never been a big seller. John F. Gregory John F. Gregory (1927–November 14, 2009) was an American optical engineer and a popularizer of amateur telescope making . He is credited with the design of a version of the Maksutov telescope called the "Gregory-Maksutov telescope". John Gregory was born in Cleveland, Ohio in 1927. He earned bachelor's and master's degrees in engineering from

400-456: Was originally envisioned as a 5-inch (130 mm) telescope, but it was decided a telescope of that size would not fit the market they were aiming for, since it would be too heavy and expensive. The Questar 3.5” entered commercial production in 1954 with ads for the model run in many astronomy, science, photography, and nature related magazines such as National Geographic , Scientific American and Sky & Telescope . The ads focused on

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