Yet Another New-To-Me "Telephoto Lens"....

[The Rigger]

Not wishing to be a Size Queen or anything, but it'll be hard to beat a 2,032mm focal length, even if it is f/10.



Hello, Jupiter...

 

[RBecker]

Wish you clear skies!

The focal length is already quite demanding, even if the other sisters from Celestron have longer focal lengths. So you there are additional steps possible …
Unfortunately the 0.7x reducer for the HD800 is only optimized for APS-C and not covering FF. But the additional 1.3 stops are maybe worth the consideration.

Waiting for your first results!

 

[halfmac]

I am sure this is a lot cheaper than the lens I saw at Kitamura Camera in Japan. If you notice the price is 4,219,100 Yen which is $29403.44 for a used 2000mm Nikkor lens. The price was reduced. But this is a very rare lens.

 

[RBecker]

I am sure this is a lot cheaper than the lens I saw at Kitamura Camera in Japan. If you notice the price is 4,219,100 Yen which is $29403.44 for a used 2000mm Nikkor lens. The price was reduced. But this is a very rare lens.

You saw there a very rare lens! Such lenses were build in the 60s and early 70s by some companies (I know also lenses from Canon) for very special pictures, like the Apollo starts.
Build in very few numbers only and already very expensive at that time. Today in good condition only for collectors with big pockets...

 

[The Rigger]

Long-FL camera lenses like that will always be costlier than an equivalent telescope; by comparison an astronomical scope will usually be of much simpler design and construction (Hubble and JWST excepted, of course). I'd also posit they don't need to withstand nearly the rigors a camera lens has to.

I've got the .7 reducer for my Celestron on my shopping list, but it'll have to wait a bit; I've got some unforeseen residential expenses to deal with first. And First Light with the 800 will have to wait, too.