Rodger W. Gordon’s Thoughts on the Tele Vue-85 and Questar 3.5″
Rodger W. Gordon has been an amateur astronomer since 1952 and has written over 300 articles for various amateur astronomy publications. Having owned hundreds of eyepieces, he has been known as the “Eyepiece King” of the hobby. In his long career, he has worked for Edmund Scientific, Vernonscope, Optical Techniques, and has consulted for Questar.
At the Northeast Astronomy Forum (NEAF) in April 2007, we introduced the 13mm Ethos 100° eyepiece. The overwhelmingly positive response to it at ensuing star-parties led me to explain why the view elicited so many enthusiastic “WOW!” comments in an essay on our website “The Majesty Factor – The Nexus of Contrast, Power, Field” (also on our mobile site). As an example of the enthusiasm, I included the following:
Right after NEAF, Rodger Gordon, a well-known “eyepiece junkie,” wrote me: “Definitely the finest wide-angle eyepiece I’ve ever seen. If God is an astronomer, this is the wide-angle eyepiece he’d choose. You can quote me.” Thanks, Rodger.
Knowing Rodger’s long experience with astronomical equipment, and the fact that we both own Questar 3.5″ telescopes, he sent me the following letter, written July 17, 2020, about comparing his Questar 3.5″ to his son’s Tele Vue-85. I like to call the Tele Vue-85 my “Goldilocks” telescope because it’s just the right aperture and size for everything from a quick “no excuse not to go out” observing session to a full night of enjoyment. However, if I judged telescopes by their sheer beauty and elegance, I guess I would rate my Questar as the “Majesty Factor” winner 😉 .
Dear Al:
On June 26, 2020 my son (here on a visit) compared his Tele Vue-85 to my 3.5″ Questar with its 1/67λ RMS optics. My son also has a 3.5″ Questar. We had seeing of 8-9 on the 0-10 ALPO scale (0 worst, 10 best). Favorably placed were the lunar craters Theophilus, Cyrillus, and Catharina. We examined these craters for 1 hour and 15 minutes, sometimes using a Schott OG-530 yellow filter (available from Edmund Optics).
Magnification on the Questar 110x, on the Tele Vue-85 – 100x. The image quality in both scopes is superb – no hints of chromatic aberration in either scope. Crater detail equal in both with or without the filter. The image was somewhat brighter in the TeleVue-85 probably due to the fact my Questar has standard magnesium fluoride coatings and the slightly higher power used on the Questar. I know you have a variety of scopes including a 3.5″ Questar so I thought you would be interested in our comparison results.
Sincerely,
Rodger W. Gordon
Specifications:Tele Vue-85 & Questar 3.5"
| Aperture (mm) | Focal Length (mm) | f# | Max Field (°) |
|
|---|---|---|---|---|
| Questar 3.5" | 89 | 1300 | 14.6 | 0.94 |
| Tele Vue-85 | 85 | 600 | 7 | 4.4 |
