Contax RF mount Triotar

[dexdog]

I recently bought a Contax RF mount Triotar on eBay for $56. Lens was advertised as being hazy, but it cleaned up nicely once I took it apart. Anyway, the lens is in a non-coupled mount, and I have never seen one like it before. Thiele's book of CZJ lenses gives a production date of August 30, 1940 for this lens, and while the batch is mostly in Exacta mount, part of the batch was made in Contax mount. Does anyone have any information about this lens, or has anyone seen a similar mount? It fits just fine on a Contax II, and takes decent pictures in a Sony NEX 5 with Contax adapter. I have a another Triotar that has a coupled Contax mount, and it is from the same batch as the non-coupled mystery lens. Pics are available on the following link. The first pic shows the coupled mount next to the uncoupled one. The notch in the rim seen in pic #5 fits the focus lock pin of the Contax camera.

http://chobe.smugmug.com/Other/135f4contax/20941643_bw96zv#!i=1663661253&k=b5ZnnH2

 

[Highway 61]

Couldn't it be a Triotar designed to be used on the equivalent of the Visoflex for the Contax RF system ?

 

[dexdog]

Couldn't it be a Triotar designed to be used on the equivalent of the Visoflex for the Contax RF system ?

The Flektoscop idea sounds reasonable, given that you would not need a coupled mount to focus. I will have to try it out.

 

[sevo]

Couldn't it be a Triotar designed to be used on the equivalent of the Visoflex for the Contax RF system ?

IIRC the original Flektoskop had a special mount, and the Panflex (which had a regular Contax outer bayonet on front) wasn't released until ten years after that lens. But there also was a macro kit made up of bellows and a barrelled ground glass that could be attached for focusing in place of the camera, which had a regular bayonet. However I'd consider it very unusual for a macro lens to be uncoupled but still have a regular helical reaching infinity, the dedicated bellows head lenses I know of have no focusing at all.

I think the most likely reason is that the lens was part of a batch provided for some cost-conscious (institutional) buyer who only needed infinity (or preset scale) focusing - whether for aerial recon use or on some kind of documentation rig.

 

[Highway 61]

I think the most likely reason is that the lens was part of a batch provided for some cost-conscious (institutional) buyer who only needed infinity (or preset scale) focusing - whether for aerial recon use or on some kind of documentation rig.

Sounds legit, yet I wonder whether this very lens may focus correctly or not when mounted directly on a Contax RF : the optical register at infinity would match the one of a SLR system. The regular Triotar is quite shorter than this one.

 

[dexdog]

Sounds legit, yet I wonder whether this very lens may focus correctly or not when mounted directly on a Contax RF : the optical register at infinity would match the one of a SLR system. The regular Triotar is quite shorter than this one.

I have a rangefinder-coupled version of the 13.5cm Triotar, and it focuses fine on a Contax II, even to infinity. The lens must have been modified from the Exacta optical register to allow it to focus accurately on a Contax. Also, I think Sevo is correct that the Flektoscop has a different mount than the Panflex (I have a Flektoscop, but not a Panflex). Given the August 1940 date of manufacture I was wondering whether this lens may have been intended for aerial reconnaissance, given that it would be used at infinity focus all the time.

 

[Highway 61]

I just realized this is a not so common 135mm Triotar not the well known 85mm one.

For the 85mm one, there is a huge difference between the Contax RF and Exakta ones as for the length of the outer barrel, hence my confusion.

The aerial reconnaissance purpose sounds fine.