Confused about T-mount + picture

[TrueLoveOne]

I have the following problem:

Last week i bought a few lenses, among them is a Tamron Converto 2.8/135 / 5.5/225. The lens itself has a detachable mount, like a t-mount i thought. The T stands for Tamron after all.....
Unfortunately mine has an Exakta adapter and not the original M42 base which will fit the dedicated extension tube to convert it to a 5.5/225 lens.

Now: my usual t-mount rings are all the same, measuring 49mm on the inside, without the threaded flange, the Tamron measures 50mm at the flange, which is not detachable. This simply means i cannot get my t-mounts on this lens to give it a go.....

Any good explanations on t-mounts? I could not find any myself..... are there different sizes?

Thanks!

picture:

[calvin83]

It is not in standard T/T2 mount.
http://cameracollector.proboards.com/thread/7918/tamron-converto-135mm?page=1

[TrueLoveOne]

Just posted a quick picture.

As you can see it's the later type, it's flange where the Exakta adapter goes is not removable from the lens. What i need basically is the M42 adapter instead of the E-adapter in the picture. But apparently this is not the usual T-mount size.
The extension tube has M42 thread on both sides, so one could quickly move from 135mm to 225mm.

[bernhardas]

Googling tamron converto produces literally as the first link the original leaflet here:

http://cameracollector.proboards.com/thread/7918/tamron-converto-135mm?page=1

It is NOT a t-mount. But a set in itself.

Welcome!!!!!!!!

[TrueLoveOne]

Same link, second time, thanks! I started googling about t-mounts of course.....

Well: problem solved here: a large plumbers tool and some force..... of came the ring. Now it's a normal t-mount.....

Extension tube is t-mount thread as well....

Feeling quite stupid now.....

[visualopsins]

This is the original T-mount, an early version of it. They came in different sizes. P.S. T in T-mount has not been proven to stand for Tamron.

[bernhardas]

[TrueLoveOne]

[mo]