[Oldseabee]

Hi, I don't know if this the right thread to ask about this lens. I'm watching Meade 1000mm-f/11 mirror lens. I have a t-adapter for my K-5 that I've used with our telescope. This lens has a couple of adapters with it but I don't know what they're for. Anybody have any thoughts? Jim

[Not a Number]

Pictures or links would help.

Typical adapters are for T-mount, eye piece diameter conversion and right angle.

[Oldseabee]

Here's the link to the auction. Jim
Mease 1000mm f/11 Mirror-Lens W/Case - shopgoodwill.com

[timw4mail]

Pictures or links would help.

Typical adapters are for T-mount, eye piece diameter conversion and right angle.

Here's the link to the auction. Jim
Mease 1000mm f/11 Mirror-Lens W/Case - shopgoodwill.com

Judging by the pictures, you have right angle adapter, anyway.

[Pentax Syntax]

Looks to be a Maksutov Cassegrain design like the ETX 90. My guess is that everything is going to be T mount threaded. Many adapters exist. Not great for routine photography at f11 but makes a nice little spotting scope.

[Not a Number]

The black and white tube is the spotting/aiming scope. It looks like the mount for the scope is missing. The camera adapter which is an extension tube with a T thread on it appears to be missing too, but you can probably get this from Meade.

Edit: the spotting scope mount may be there. Looks like part is still on the main scope and perhaps the rest in the case.

The T-thread adapter is a tube about 2 inches long with a 35mm female threads (screws on scope) and a male T-thread.

[DeadJohn]

...lens has a couple of adapters with it...

TLDR version, educated guess that the rear is M35 threads and there are no other adapters.

I'm always curious about telescopes.I looked at the auction photos and see these parts:

1. Telescope, with unknown threads on back.
2. Case
3. Diagonal for optical viewing. A black part with "Meade" and "Japan" printed on it.
4. Finder scope. Mostly white part with "5 x 21mm" printed on it. A 2nd photo of it has "Japan" on the opposite side".
5. Eyepiece. "MA25mm". The auction text mentions a 2nd eyepiece.

I'll assume the eyepiece and diagonal are 1.25" standard. M42 or T-threads (T is also 42mm wide, but different thread pitch than M42) would therefore be wider than the diagonal is, so the threads on the back of the scope must be narrower than 42mm. If the back of the scope is 42mm then there's possibly a missing adapter to go from the back of the scope to the diagonal but that would be weird product engineering. I emphasize that this is guesswork, but I strongly suspect that the threads are narrower than M42 or T.

Here's a discussion of a similar telescope which may or may not be the same exact model in the auction. The original poster describes the rear cell as 1.375" or 35mm. Meade 1000mm f 11 Mirror Lens

Let's assume the M35 rear thread. You could use an M35 to T-thread adapter, then possibly a T-extension to reach focus when the diagonal is not in the optical path. Or maybe this one piece will work; I don't see thread specifications in the description by I think many ETX scopes are M35. High Point Scientific support is great, so if you win the auction measure the threads, then contact them. Meade 64 T-Adapter for ETX 90-125 Telescopes - 07363

Good luck with the auction.

[Oldseabee]

I haven't decided if I'm going to bid on it. Kind of depends on how aggressive bidding gets. I've seen people pay more for something than it costs new. I've got three spotting scopes now one with a Gorsky phone mount that works surprising well. I was thinking about pictures of the moon and such. Jim

[richfam]

I have this exact "lens" – it uses a tube with T-mount to attach to a camera, but I can't see that in the photos. It uses the small .965" eyepieces when used as a spotting scope.

Unfortunately, it's a terrible telephoto lens: the photo shows a sample uncropped photo I took with it, using my K-70 and a sturdy tripod and focusing as carefully as possible. But there's nothing really sharp in the photo; and that's the best your probably going to get. With any sort of moving subject you'll never get it in focus.

It might work a little better on a full-frame sensor… but I bought this back in the film era and never really got a usable 35mm negative with it.

It would probably work OK as a spotting scope (mine didn't come with an eyepiece so I've never tried it myself), but I can't recommend it for use as a telephoto lens.

[DeadJohn]

It might work a little better on a full-frame sensor

FF is too large a sensor for Maksutov Cassegrain and Schmidt Cassegrain telescopes. The corners vignette horribly because the sensor is larger than the opening on the back of the scope.

[timw4mail]

I have this exact "lens" – it uses a tube with T-mount to attach to a camera, but I can't see that in the photos. It uses the small .965" eyepieces when used as a spotting scope.

Unfortunately, it's a terrible telephoto lens: the photo shows a sample uncropped photo I took with it, using my K-70 and a sturdy tripod and focusing as carefully as possible. But there's nothing really sharp in the photo; and that's the best your probably going to get. With any sort of moving subject you'll never get it in focus.

It might work a little better on a full-frame sensor… but I bought this back in the film era and never really got a usable 35mm negative with it.

It would probably work OK as a spotting scope (mine didn't come with an eyepiece so I've never tried it myself), but I can't recommend it for use as a telephoto lens.

While I can't speak for this lens, mirror lenses are more difficult to focus exactly, but when you actually manage to nail focus they can surprise you.

[Not a Number]

I have the Celestron C90 I bought in the 80s. Inferior in every way to the Meade. I never noticed any vignetting when I used it on my film cameras. Because of the nature of the lens they have uneven brightness across the frame to being with. Most notable with the doughnut "bokeh balls". Putting a big black dot in the middle of any lens is going to have an effect.

It's difficult to nail the focus and the results from my C90 always seem a bit soft but a better view screen or liveview (not an option on my K10D) would help.

Improvising a lens hood with some black paper and a rubber band helps too.

The ETX C90 adapter is supposed to be compatible.

[ZombieArmy]

I have this exact "lens" – it uses a tube with T-mount to attach to a camera, but I can't see that in the photos. It uses the small .965" eyepieces when used as a spotting scope.

Unfortunately, it's a terrible telephoto lens: the photo shows a sample uncropped photo I took with it, using my K-70 and a sturdy tripod and focusing as carefully as possible. But there's nothing really sharp in the photo; and that's the best your probably going to get. With any sort of moving subject you'll never get it in focus.

It might work a little better on a full-frame sensor… but I bought this back in the film era and never really got a usable 35mm negative with it.

It would probably work OK as a spotting scope (mine didn't come with an eyepiece so I've never tried it myself), but I can't recommend it for use as a telephoto lens.

I don't know, I've gotten some good shots with it. It's also great for looking at the planets.

Single shot of the moon.

[richfam]

I don't know, I've gotten some good shots with it. It's also great for looking at the planets.

Single shot of the moon.

I agree that your moon shot looks pretty good... but I never got a single acceptable image from mine.

Possible explanations:

(A) My copy is defective in some way; misalinged maybe.

(B) Your moon shot was, obviously, taken at infinity focus. Powerful telephotos generally can't use infinity focus with terrestrial subjects, because of the problems you encounter when trying to shoot through miles of turbulent atmosphere; everything I tried to shoot was 100 yards away or less. So maybe the lens is OK at infinity focus, and not so good with close subjects.