[lr_photography_soflo]

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Hello! New to the forum and I need help. I want to adapt this lens (see image) to my Canon T6, however, I can't figure out what kind of mount this is. Any help would be appreciated.

Attached Images

 

[twilhelm]

Someone may know based on the photo, and it may be an m42 mount, but can you provide a photo of the base of the lens?

[Not a Number]

It's either an M42 or T2 mount. Both are the same diameter but with different thread pitch. It is important to use the correct mount otherwise you can damage the threads on both the adapter and lens.

Brand name and any other information you can provide about the lens would help. You may check the rear cap. If it is threaded and for M42 it may be marked M42 or "P" for Pentax. More photos of the lens mount would help.

[vonBaloney]

Doesn't really look complete. Looks like a bellows lens or enlarger lens -- does it have an aperture? Lets see the other side of it and the face ring if any.

[lr_photography_soflo]

Someone may know based on the photo, and it may be an m42 mount, but can you provide a photo of the base of the lens?

SANKYO KOHKI Komura 200mm f3.5 Japan #2138243 and here's the eBay listing (SANKYO KOHKI Komura 200mm f3.5 Japan #2138243 | eBay)

[UncleVanya]

Try this...

SLR Lens Mount Identification Guide

[disconnekt]

Try this...

SLR Lens Mount Identification Guide

You beat me to it, I was just about to post this link lol

[BigMackCam]

Looking at the eBay photos, and considering the focal and physical length, I've a feeling that's a T-mount lens to which you'd normally fit an adapter for M42 or other popular mounts of the time... but it looks like that adapter might be missing (which is no big deal, as they are readily available).

I'm not 100% certain of this, but it's my best guess currently...

Further research suggests it may be an M39 thread mount intended for Leica Visoflex, and requiring a (proprietary?) "Komura Uni. Adapter" for other cameras...

LENS PORN: Sankyo Kohki KOMURA 200mm f/3.5 | Lens Shatter By Rattus

[Not a Number]

Scrolling through the posts on mflenses.com it is quite complicated. Apparently Komura made many, many versions of this lens.

Some are M39 mount.
Some are T-mount.
Some had Komura's interchangeable mount (Komuranon).
Some had different type mounts on them from the factory including M42.

The thing to do is measure the diameter of the rear thread (outside). If it is 42mm than it is either T-mount or M42. If it is 39mm then you need an M39 to EOS adapter.

Anything else you are pretty much still in the dark.

If it's 42mm you could:

• take a 50/50 chance and buy a T2 or M42 to EOS adapter and hope it fits - give up if there is the slightest resistance.
• buy one of each adapter because if you buy a lot of manual focus lenses sooner or later you use both.
• take it to a good hardware store and see if they can measure the thread pitch - 0.75mm for T, 1mm for M42.

One thing that seems constant is the quality of the optics appears to quite good.

[UncleVanya]

Good luck and please let us know what you find out.

[stevebrot]

Further research suggests it may be an M39 thread mount intended for Leica Visoflex, and requiring a (proprietary?) "Komura Uni. Adapter" for other cameras...

Yes...the Unidapter adapter is missing, the the lens is intended for SLR use (has preset diaphragm) though it would also work for Visoflex with appropriate adapter. The mount adapter is fairly long and would make up missing length on the pictured lens. I can't say how the Series III hood comes into the picture.

Edit: Here is a link to a similar lens with M42 mount attached...

https://www.ebay.com/itm/Sankyo-Kohki-Japan-Komura-200mm-F3-5-PENTAX-M42-SCR...torefresh=true


Steve

[BigMackCam]

Scrolling through the posts on mflenses.com it is quite complicated. Apparently Komura made many, many versions of this lens.

Some are M39 mount.
Some are T-mount.
Some had Komura's interchangeable mount (Komuranon).
Some had different type mounts on them from the factory including M42.

The thing to do is measure the diameter of the rear thread (outside). If it is 42mm than it is either T-mount or M42. If it is 39mm then you need an M39 to EOS adapter.

The physical length of that lens, for a 200mm, tends to suggest that it's still short of an adapter with reasonable extension... Could be it's a T-mount or VisoFlex version, but either way, missing the uni adapter - I think!

[Not a Number]

I don't know. The shots online I can find of the Uni mount show it uses a bayonet, not a screw mount.

This could be a version of the lens for a Bronica medium format camera - adapters needed.

[stevebrot]

The physical length of that lens, for a 200mm, tends to suggest that it's still short of an adapter with reasonable extension... Could be it's a T-mount or VisoFlex version, but either way, missing the uni adapter - I think!

There is no T-mount version though some forum discussions refer to the Unidapter as T-mount (Unidapter is 44mm). I spent a fair amount of time in Komura-land last month researching a 135mm I have in Exakta mount. Manual and preset models are either fixed mount or Unidapter. FWIW, Unidapters are quite rare unless attached to a lens. I would pass on this one.

The physical length of that lens, for a 200mm, tends to suggest that it's still short of an adapter with reasonable extension... Could be it's a T-mount or VisoFlex version, but either way, missing the uni adapter - I think!

There is no T-mount version though some forum discussions refer to the Unidapter as T-mount (Unidapter is 44mm). I spent a fair amount of time in Komura-land last month researching a 135mm I have in Exakta mount. Manual and preset models are either fixed mount or Unidapter. FWIW, Unidapters are quite rare unless attached to a lens. I would pass on this one.

Note: The camera wiki says that some lenses were made in T-mount, though I don't remember seeing such in the surviving Komura catalogs and lists. Anything is possible, however.


Steve

[stevebrot]

I don't know. The shots online I can find of the Uni mount show it uses a bayonet, not a screw mount.

There are two types. The earlier version for preset lenses attaches with screw threads and secures with a grub screw. The later version is bayonet and is used with auto aperture Komura models.

Edit: The first version was called Unidapter and the second Auto Unidapter. Some online references call the former unimount.

http://camera-wiki.org/wiki/Sanky%C5%8D_K%C5%8Dki#Komura_Unidapter_preset_lenses


Steve