Leica screw mount lens - Steinheil Munchen 5cm f/2.8 collapsible Triplar....prototype?

[kkdanamatt]

I can't find any information about this lens. One source says that it's a prototype.
Any other information would be appreciated.
Thanks.

 

[Sonnar Brian]

I did a look on Ebay to see if the "5cm F2.8 Triplar" was made in a different mount- could not find it. The "Triplar" lens could be found, but is uncommon.

I would guess this is a prototype.

Lens Steinheil Makro Cassarit 3,5/50mm for Bellows Camera Exakta | eBay

Tracing number.

www.ebay.com

I did find a barrel that could be adapted in a similar fashion.

Cool, unique lens- let's see some pictures with it.

 

[mdarnton]

I don't know how someone could call such a thing a prototype without solid documentation of that from the manufacturer. It's a frankenlens.

 

[Miles.]

One sold at a Leitz Photographica auction in 2008.

Looks genuine to me.

 

[kkdanamatt]

One sold at a Leitz Photographica auction in 2008.

Looks genuine to me.

Thanks for the info. I thought it wasn't a prototype because it appears to have a legit serial number. It must be somewhat rare because it's the only one I've ever run across in over 50 years. I tested it on a Sony digital camera and the results are OK wide open, but nothing extraordinary.

 

[Sonnar Brian]

I don't know how someone could call such a thing a prototype without solid documentation of that from the manufacturer. It's a frankenlens.

It's easy- the parts are not available in a different mount that would lend themselves to being transplanted to a custom-made or re-used LTM mount.
If the 5cm F2.8 Triplar was available on a different camera, or in Paxette mount-

Steinheil Munchen Cassarit 50mm f2.8 Paxette Mount Lens Screw Mount #G631 | eBay

We want you to receive the item as quickly as possible! Local Pickup.

www.ebay.com

Would be easy to convert. I could not find donor lenses like this one on Ebay or anywhere else. I've adapted a lot of lenses to Leica Mount, including Paxette mount.

I did find this page:

https://www.oldlens.com/steinheil%20triplar%205cm%20f28.html

And-

Steinheil: 50mm (5cm) f2.8 Triplar (M39) Lens Price Guide: estimate your lens value

Steinheil: 50mm (5cm) f2.8 Triplar (M39) lenses information and completed auction prices

collectiblend.com

 

[Sonnar Brian]

On this example lens- the machining looks a bit rough on the mount. The distance scale is not fully marked- looks like a single hardware stop used in the design. I'm guessing by looking at the Cam that it is not focused past infinity. The picture of the one I found on the web looked more refined.

 

[xayraa33]

It looks like an interesting lens.

 

[kkdanamatt]

Thanks to all for your comments.
My lens is in the same serial number range of the lens that was sold at the Leica auction in 2008.
I'm curious to know when and how many Steinheil 50mm f/2.8 Triplar lenses in Leica thread mount were manufactured.

 

[Sonnar Brian]

The website I found gives an optical diagram, labels "an Inverted Tessar". Would be nice to know more specifics. Now I need to look for one of these... My guess- this lens is an improved Cassar Triplet where the front element is divided into a cemented pair, a 2-1-1 design. Minolta did something similar with several of their lenses- divided the front element into a cemented Triplet, for a 3-1-1 design. Schneider improved the Tessar in their Xenar-Special by dividing the front element into two elements of lesser power, a 1-1-1-2. The latter: I found one loose, with a regular aperture ring for $30 at a camera show. That lens- I made into an LTM RF coupled lens using a Canon focus mount. SN puts it at Wartime production, fully coated. I could not find any Triplar 5cm F2.8 mounted on any cameras, I would have bought it just to take apart. Like the Karat-Xenar.