44mm T-mount? What is this animal?

[xkaes]

I just ran across what I thought was a T-mount for Minolta cameras -- but it's not.

It looks just like a T-mount, with a Minolta bayonet on the rear (with an aperture control tab for the lens), but the thread on the front is 44mm, not 42mm as with a standard T-mount (or Sigma Y-S mount).

It's not marked in any way.

Anyone have a guess as to what it is?

 

[Paul Howell]

If it's a 44 screw mount it is for Miranda, not sure how far back but at least starting, maybe earlier, Sensormate, Mirandas had duel mounts, a 4 claw bayonet and an inner 44mm screw mount. I don't know if Miranda made any 44mm lens, in EE mount the longest lens they made was 200, early bodies they made 300 and 400, these were bayonet mounts. I've seen long lens, 400 and 800 from 3rd party lens in 44mm. Although 44mm lens would mount on the Miranda EE it would not meter at all, with the earlier Senormate bodies might be used in stopped down metering mode. Although Miranda designed lens in house, lens were made by contract with a number of lens makers. Miranda's parent company AIC also owned Soligar which also sold some of Miranda's designs under it's brand, I've seen 44mm 400 with Soligar badge. .

 

[xkaes]

Thanks.

I know that older Miranda lenses are 44mm, but this adapter has a 44mm FRONT thread and a Minolta-mount on the REAR, not a T-mount on the front and a 44mm thread on the rear for Miranda cameras.

Assuming the pitch is the same, I could put Miranda 44mm lenses on a Minolta camera, but it wouldn't focus on anything further away than a few inches.

 

[BobD]

For bellows?

 

[Paul Howell]

Must be for some sort of specialty application, as noted by BobD, bellows extension tubes, maybe microscope adaptor? Maybe a one off for a telescope?

 

[xkaes]

For bellows?

There are bellows and slide copiers that use the 42mm T-mount, and there might be some that use 44mm, but I don't know of any.

The odd thing about this 44mm adapter is that it is for Minolta cameras and has an auto-diaphragm linkage to connect the camera and the lens -- a lens with a 44mm rear thread. The 44mm front of the adapter has a diaphragm pin -- the same as the Pentax ES & Sigma YS lenses, but they are 42mm, not 44mm. Miranda's 44mm lenses did not have this so this adapter was not for Miranda lenses -- and I don't know of any auto-bellows that used a PIN configuration to set the diaphragm of a lens.

Perhaps a photo or two will help figure this out.

It was obviously factory made -- and undoubtedly was designed for cameras other than Minolta, since it is an adapter.

 

[Donald Qualls]

designed for cameras other than Minolta,

Wouldn't that be designed for Minolta cameras to use other lenses?

 

[xkaes]

You're right, but the lenses either have to have a 44mm rear thread -- and have an flange focal length off-set, like the 42mm T-mount, in order to focus to infinity -- or be a close-focusing lens like a bellows lens. I can't think of anything like that -- but they must exist.

 

[wiltw]

Maybe this is the reason...C-mount. C mount is a type of lens mount commonly found on 16 mm movie cameras, closed-circuit television cameras, machine vision cameras and microscope phototubes.

IP67 C-Mount Lens Tube, Inner ⌀: 44mm, Inner Length: 68.5mm

LUCID's IP67 lens tubes are compatible with Triton and Atlas IP67 cameras. Connect an IP67 lens tube and IP67 cables to the camera for dust and water protection

thinklucid.com

 

[Dan Fromm]

Maybe this is the reason...C-mount. C mount is a type of lens mount commonly found on 16 mm movie cameras, closed-circuit television cameras, machine vision cameras and microscope phototubes.

IP67 C-Mount Lens Tube, Inner ⌀: 44mm, Inner Length: 68.5mm

LUCID's IP67 lens tubes are compatible with Triton and Atlas IP67 cameras. Connect an IP67 lens tube and IP67 cables to the camera for dust and water protection

thinklucid.com

I dunno. The C-mount spec is 1" x 32 tpi thread and 17.526 mm (0.69") flange-to-film distance.

 

[xkaes]

Right. C-mount is WAY smaller than T-mount and this adapter's front thread is BIGGER than T-mount. And besides the REAR of the adapter is to put the lens on a full-frame 35mm Minolta SLR -- a format much larger than C-mount lenses cover.

By the way, Minolta did make a C-adapter -- to put Minolta 35mm lenses on movie cameras.

 

[BobD]

The Fujita 66 and its clones had a 44mm screw mount.

 

[wiltw]

Did a bit of added research and found this

http://rick_oleson.tripod.com/index-99.html

"From about 1955-1960, Miranda cameras used a 44mm thread mount as shown here. The M44 screw thread was kept as part of the bayonet mount design, so that these lenses could still be used on later Miranda cameras. Some new lenses continued to be offered in the M44 screw mount as late as 1967, and it also remained the standard mount for bellows, T mounts, and other accessories that did not require aperture coupling. "​

 

[Paul Howell]

That what jumped to until OP remined that I did read his post carefully, it has a Minolta MD mount with a 44mm front, some sort of adaptor.

 

[xkaes]

That's an interesting quote, but who knows who wrote it. Sure, Miranda started out with 44mm rear thread lenses, but would any company make adapters for these lenses to be used on other cameras -- that only allowed for macro photography? Hard to believe.

The other part of the quote, "it also remained the standard mount for bellows, T mounts, and other accessories that did not require aperture coupling. " makes even less sense.

The standard T-mount is 42mm, not 44mm -- and while the standard T-mount does not offer aperture coupling, the adapter I have DOES.

What I have is an adapter with a 44mm front thread, and a Minolta SR rear bayonet -- with aperture control of the lens by the camera. I'll post pictures later today -- which will probably help.

 

[xkaes]

That what jumped to until OP remined that I did read his post carefully, it has a Minolta MD mount with a 44mm front, some sort of adaptor.

To be exact, the rear of the adapter is a Minolta SR mount. There is an auto-diaphragm connection -- to stop-down the aperture of the lens at the instant of the exposure -- but it does not have MC or MD capability.

 

[xkaes]

Here are photos.

From the side it looks like a T-mount to Minolta adapter.

The rear shows the Minolta SR mount with a pin that is pushed by the aperture lever in the camera -- to stop-down the aperture in the lens (which t-mount lenses DO NOT have!)

The front shows the 44mm screw-mount -- not a 42mm T-thread -- AND the silver tab pushes in on a pin in the lens -- a lens with a 44mm thread.

BEATS ME!!!!

 

[Paul Howell]

Im not familiar with SR mount, does this adaptor bring out the lens to flange distance that matches Miranda?

 

[xkaes]

Minolta & Miranda are very similar in regard to Flange distance. This adapter much thicker as you can see from the side view -- and would just add extension. It very similar in depth to a T-mount. Putting a Miranda lens on this would be great for macro work, but no one is going to make an adapter to put Miranda lenses on Minolta cameras for macro work at a fixed distance. Plus, there would be no point in putting the aperture connection in the adapter because that is completely different from how Miranda lenses operated.

 

[Paul Howell]

44mm lens are somewhat rare, have only a few, and you noted Miranda M44 were not coupled.

 

[xkaes]

The apertures in Miranda lenses are coupled to the camera, but not in the way that this adapter is. On the camera side is the sliding Minolta lever. On the lens side is a tab that pushes a pin on the back of the lens -- very similar to Pentax lenses for the ES, and similar cameras with automatic diaphragms. Miranda lens coupling is totally different -- with rotating linkages like Canon and Nikon.

 

[xkaes]

Thanks to someone -- apparently not on this FORUM -- I've been informed that my mystery adapter is a "T-mount" even though it has a 44mm thread. But it is NOT a Miranda product as I originally supposed.

Back in the '60s, Kalimar created their own "T-mount" with a 44mm thread -- and lenses from 25mm to 400mm to go with it. The main difference was that it included auto-aperture control -- which needed a couple of extra millimeters.

That's what this mystery is:

Here's where I found additional info:

http://forum.mflenses.com/auto-t-the-most-obscure-interchangeable-mount-t10869,highlight,kaligar.html

I'm not going to run out and buy any Kaligar lenses, but I'm sure someone has an interest.