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07-20-2007, 09:42 AM   #1
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Can anyone give me a some info. on T-mounts?

What IS a T-mount?

Were lenses made specifically with this mount?

Were/are there any real gems?

Are there adapters for current cameras?

All info. appreciated- or point me somewhere I can get some answers.


07-20-2007, 10:14 AM   #2
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Wow, a question I can answer.

A T-mount or T-ring or T-adaptor refers to a simple round adaptor that converts various cameras to one thread size. Each T-ring is specific to a camera, I have several Pentax K T-rings. I used one for my K1000 film SLR and now use them for my K1x0D cameras. Typical cost is $15.

What for? I have several telescopes that have T-ring threads. Telescopes use T-threads since this standard can be used for almost any SLR with the right T-adaptor. We also have some generic lenses, such as a Quanteray 500mm plus doubler that have T-ring threads. It is a cheap lens, and the company chose to make one T-thread version rather than a version for every camera.

If given a choice one would prefer a lens to have the right fittings for your camera in the first place. When you don't have a choice then a T-ring is used. A T-ring will not adapt a Nikon lens to a Pentax, just a generic lens to Pentax.

Note: T-Rings are used with manual lenses, they do not pass through any electrical signals.

Last edited by LeoTaylor; 07-20-2007 at 10:15 AM. Reason: Typo
07-20-2007, 02:48 PM   #3
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QuoteOriginally posted by Tom Lusk Quote
Can anyone give me a some info. on T-mounts?

What IS a T-mount?

Were lenses made specifically with this mount?

Were/are there any real gems?

Are there adapters for current cameras?

All info. appreciated- or point me somewhere I can get some answers.

I believe it was originally designed by Tamron in the old days of screwmount lenses (hence the T name), but for the past two decades in the era of bayonet lenses, T-mount is usually used for mounting a camera to a telescope or microscope. As a result, T-mount is usually though of as meaning "telescope mount".
07-20-2007, 07:16 PM   #4
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T-Mount lenses are not as readily available as in the 60's to 90's, but are sometimes a bargain. Mostly used for 200mm lenses and longer, but also available in all fl's.
I picked up a 350mm f/5.5 about 12 years ago that remains to this day one of the sharpest lenses I have ever owned.
The beauty of them is that they are very compact and lightweight most of the time and with another adapter the lens can be used on a different camera type.


07-20-2007, 09:02 PM   #5
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Here's how I remember it

Lens makers (like Soligor or Vivitar as well as Tamron) would make a somewhat universal lens and one could purchase a T-mount so it would fit on your specific SLR body. That way, if you had two different makes, or changed makes, you could buy the T-mount to fit your camera. Those lenses were not like todays lenses. Most of them, you wouldn't want. Ebay prices reflect that demand or lack of it.

They might have been called T4 mounts. I'd have to go and dig out my 28mm and 135mm t-mount lenses.
08-07-2007, 09:05 AM   #6
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Tom, I also use one for my screwmount Bellows to mount it on the camera. The T mount is an M42 thread on the outboard end and a K mount on the camera end. Since the added distance between the bellows and camera (about 1 cm) won't affect infinity focus and only adds a little to the magnification. Allows me to use these older extension tubes and bellows with almost any M42 lens on the screwmount bellows.
08-14-2007, 07:43 PM   #7
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a Tmount is 42mm yes but the threading is slightly different than the M42. you can screw on an M42 to K adapter onto the tmount only partially and the ring will stop turning as the differently spaced threads lock up. You'll have to get an actual tmount adapter.

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