Is this too good to be well a good buy

[supernova1965]

Hi all can you tell me what you think of this deal

http://www.ebay.com.au/itm/Polaroid-900mm-1800mm-Mirror-Lens-Nikon-D3100-D3200-D5100-D7000-D700-D800-D4-/140877839101?pt=Camera_Lenses&hash=item20ccf93afd&_uhb=1#ht_2540wt_992

[raymo]

hi Warren,
The bottom has fallen out of the astronomical/ photographic
equipment market, with all sorts of gear, new and used, for sale at
ludricrously low prices, and often not selling, so this 900mm lens may very well be quite good. As long as you are not expecting Leica
quality, I think that you may very well be happy with it.
I hasten to add that I am not actually recommending that
you buy it; I'm just giving you my thoughts on the matter. In other
words, please don't hold me responsible if it all goes belly up.
regards raymo

[Wavytone]

There are others too...

http://www.ebay.com.au/sch/i.html?_sacat=0&_from=R40&_nkw=MTO+lens&LH_PrefLoc=2&_arm=1&_armm=63&_ruu=http%3A%2F%2Fwww.ebay.com.au%2 Fsch%2Fi.html%3F_sacat%3D0%26_from% 3DR40%26_nkw%3DMTO%2Blens%26_arr%3D 1

I used to have an MTO-1000A, big and heavy but optically excellent - the secondary mirror is reasonably small and it served quite well as a small telescope. The lenses in the early ones (1958) weren't coated but later ones from the 1970's had MgF coatings.

[bojan]

Those Catadioptric Maksutov lenses may be a good buy, but, as raymo said, just don't expect the perfection.

I have something similar (MTO-1100A (http://www.ebay.com.au/itm/MTO-1000A-10-5-1100-unique-huge-mirror-lens-m42-full-kit-/221172000839?pt=Camera_Lenses&hash=item337ee0e847)) and I am happy with it, but, having said that, I needed to do some repair, to improve the performance, see thread here, #8 (http://www.iceinspace.com.au/forum/showthread.php?t=102358&highlight=MTO+modification)..
However, it is quite good for visual (lower magnifications), as it is very portable.
I also used it to take photos of Total Solar Eclipse in Cairns last year.

[rogerco]

I brought the 800mm without the 2x converter, haven't used it much yet, but first shot were ok,issue with focus which was difficult because of stiffness in rotating barrel but that is often better than too loose. Main issue was with lens mount which was a bit slack. But the real issue is hanging all that weight off a camera lens mount. Look for the lenses that have a tripod mount built in. I plan on building some sort of combined lens camera support.

But hey, for $120 I paid for mine it's worth experimenting :thumbsup: