Many thanks to Michael and Kay Heem, I was able to get my hands on a Questar at one of the local cash converter store. This was the Duplex 3.5” model and came with a brown box, solar filter, two eyepieces, and tripod legs. No power guide electronics. It was the worst Questar 3.5” that I have ever seen, basically it could not be used visually anymore, and cosmetically, it was worn. However, I thought it might make a good display item, exhibit tool for future astro events, or just for the sake of teaching how a maksutov functions. Nevertheless, I bought it and took it home for a possible restoration project. With a couple of tools at hand, cleaning solution, rust remover, metal polisher, I decided to take apart the telescope partially (since it was in such a bad condition anyway). The corrector meniscus was already corroded and filled with fungus, likewise for the Cervit primary mirror. It was a pity, since the meniscus was suppose to have broadband coatings (rather than MgFl2), and the Cervit mirror was rare in the sense that Questar stopped production of cervit in 1978 while it had ultra low thermal expansion properties. It was however superseded by Zerodur for the better models and Pyrex for the standard. I had previously owned another 3.5” before, but it was the Standard Model, though it a much better condition. However, this was a Duplex and would have been useful since it could be taken out of the cradle and mounted on any tripod with a 3/8” or 1/4” socket, or even as a piggyback or guiding scope.
Below are some of the pictures taken when the scope was taken apart, and the condition of the optics set. The last few pictures shows it assembled again, after a round of polishing (several hours of rubbing and polishing, amazing because i had three blisters on my right hand including the thumb surface prior to seeing this Questar). Have yet to think about getting a total replacement optics set, but have contacted Questar for options.
Partial dismantling of the telescope
Corrector Meniscus
A view at the primary mirror
Internal flip mechanism and prism
Business end (after removing the prism module)
Peeking through the finder optics path, after cleaning. Prior to this, it was near opague
Telescope assembled again after initial round of polishing (for now)
