needs, I'm old enough to have seen these when new, and yes this is a mak - and there is a reason why they are rare - they weren't great, optically.
OP these were originally manufactured as a camera lens and subsequently re-packaged and badged by Celestron with minor mechanical mods to function visually. As such not particularly well corrected - they were well known for being soft. The bad news is there's no way you'll get a great image for visual astronomy let alone resolve a diffraction pattern.
It might be adequate as a finderscope but not much more.
Historically Questar made a 700mm mirror lens that (like their scopes) was in a class of its own and it inspired many cheap imitations such as this one, all inferior.
Edited by luxo II, 08 September 2019 - 06:28 AM.