Talk to me about the 5cm Spezial-Anastigmat Zeiss/Contax lens

Corran

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On a whim I bought a 5cm Spezial-Anastigmat lens. This is a fixed-focus, fixed-aperture lens, and my research has shown that it was originally supplied for an enlarger, potentially the Focomat Ic.

My question is, why does it have a Contax mount then? Was it intended to be used on the Contax I camera? It certainly looks at home on mine. Here's the problem - the "fixed focus" point is past infinity. I was thinking it'd be at infinity, or even better, at some hyperfocal point. Secondly, I'm not sure what the aperture is, but my guess is f/8. Is that just an optimal point for enlargement?

This is a strange lens/product and I'm just curious if anyone else has used it and/or has more info on it. I thought it would be a cute pocket lens. On the other hand, perhaps some sort of extension ring could be rigged up...
 
It is not unique - I've seen them occasionally on camera fairs or auctions. It will have been no enlarger lens, as there never was a enlarger with Contax mount. The ones I've noticed were, by serial, within the first years of the Contax I. "Spezial" (or later "S-") means it was a technical close-up lens, but I am a bit stumped as to which macro rig it might have belonged to - all my Contax macro stuff is late thirties or post war...

Even more odd than the lack of a helicoid (that is common on dedicated macro bellows lenses) is that it has no aperture control, as the latter is pretty universally desirable in photography. Was there a early Zeiss mirror box or macro focusing utility that took a Contax lens for a finder? There were similar fixed focus, fixed aperture lenses in Exakta mount to be used as a finder loupe on Ihagee macro rigs, on a special waist level finder that sported a bayonet in place of the chimney.
 
I do know there was a ground-glass adapter and plate holder for the Contax I. But the lack of focusing is still strange - was there an extension piece for that setup?

Also, see here near the end of the page:
http://www.earlyphotography.co.uk/site/entry_C435.html

Some sort of duplication setup? Could this be related? Looks like a Sonnar 5cm f/2 on that camera though, not the Spezial.
 
Some sort of duplication setup? Could this be related? Looks like a Sonnar 5cm f/2 on that camera though, not the Spezial.

That looks like a variable predecessor of the (fixed 1:1 ratio) Contakop. It does not sound unlikely that that lens was part of such a outfit.
 
Interesting, I've not heard of that contraption.

There seems to be something between the Sonnar and the camera in that photo. Perhaps that is the variable focusing piece one would need to use the Spezial. Hmm.
 

The Magnaphot enlarger Steve shows not only has a Contax bayonet but it could also be bought with a 5cm lens called a special projection anistigmat in Zeiss price lists from 1935 onwards.

Don't know if that's your lens or not, but it's possible.

BTW Focomat is a Leitz product and would not come with a Zeiss bayonet.

Bill
 
Yeah that's probably it. I was mistaken about the Focomat and meant the Magniphot.

Still don't know how it focused properly and why it has no aperture.
 
no focus

no focus

Corran,

None of the Contax 50's have a built-in focus. The focusing mechanism is either in the camera mount or the enlarger mount. That said, I too am puzzled by the lack of an iris diaphragm. The lens I referenced cost $14.50 vs $57 for a Tessar 3.5 5cm in Sept 1936, so something had to be left off.

The reproduction stand uses the normal 5cm lens from the Contax with various extension rings and masks as needed.

Bill
 
None of the Contax 50's have a built-in focus.

That would be right for the inner Contax bayonet lenses. Perhaps a image would have been useful, or we should have explained: The oddity of the Spezial-Anastigmats is that they are outer Contax bayonet, where lenses need a helical, if they are to focus. See here:

https://www.liveauctioneers.com/item/9712321_contax-iii-with-spezial-anastigmat-5-cm-c-1936

So they obviously belong on bellows or some other outer bayonet accessory that accounts for the focusing. If it should be a enlarger, it probably is not the Magniphot 35mm (the ones I am familiar with take inner bayonet 50mm's, so a outer bayonet lens could not be focused there), but it might have been the 120 version, which I only know in later (perhaps heavily rebuilt) versions, all with 39mm lens board, so I can't tell whether it had a Contax outer bayonet option.
 
Yep, sevo is correct, the lens bayonets onto the outer mount and moving the focusing razor wheel does nothing. I'm well-versed in the 5cm lenses w/ no helical - I own about a dozen of them :).

Well it's still somewhat of a mystery, perhaps there is some other accessory that has been lost to time? Did Contax ever make a bellows focusing unit for the pre-war Contax cameras, to shoot macro with, in conjunction with the ground glass and plate adapter?

I am going to develop some test film I shot with it now...
 
pre-war Contax bellows

pre-war Contax bellows

No they did not, at least they never showed in in their catalogues. This could be an enlarger lens for the Magniphot. The lack of a means to adjust the lens, however still bothers me.

Zeiss Ikon Catalogue 1938 P C39 describing the Magniphot states:

"Es kann jedoch auch ein Spezial-Anistigmat geliefert werden, wenn die Camera-Objektive nicht verwendet werden sollen oder konnen."

Magniphot instructions state:

"If no Contax lenses are available, the apparatus should be used in conjunction with a special 2” anastigmat. (Order No. 1454/21.) Similarly to the telephoto-lenses of the Contax, the mount of this anastigmat should be fitted to the bayonet fitting of the apppparatus (see also Contax instruction.)"

The 2" lens is what 5cm lenses were called in English. Similarly to the telephoto-lenses meant outer bayonet mounting.

Worthpoint shows a Magniphot with what may be this lens.

Bill
 
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The 2" lens is what 5cm lenses were called in English. Similarly to the telephoto-lenses meant outer bayonet mounting.

That means the helical focusing of the Contax I era Magniphot would have to move both bayonets. From the images I've seen it is impossible to determine. And I've never seen such a early one in the flesh.
 
Zeiss also made an adaptor Bestellnummer 1545/31 which was produced to fit Contax bayonet lenses onto M39-mount enlargers.
 
Sevo,

That's exactly what bothers me. Also why put a second focusing mechanism on an enlarger that can use Contax lenses?

Bill
 
Sevo,

That's exactly what bothers me. Also why put a second focusing mechanism on an enlarger that can use Contax lenses?

The Magniphot was from the Contax I period, when Zeiss Ikon did have quite a few issues with excessively complex designs, so it might be.

And the Magniphot might have been worse and/or more odd than I thought - I always believed I had seen and handled one, but going through the pictures on the net it appears the nameless Zeiss Ikon enlarger of my grandfather was a Miraphot, a 120 enlarger similar to the Focomat and Varioscop, several grades above the Magniphot.
 
This is all very interesting!

So in the interest of actually using the lens, I started tinkering...it turns out there is a small set screw on the side of the barrel that holds the actual lens in place on the bayonet mount. For reference, the lens by itself is this:

http://www.ebay.com/itm/161679971244

Now since the channel for the set screw is near the front, I flipped the lens around and screwed the set screw into the channel again, which effectively moves the lens forward several millimeters. I believe the lens is a symmetrical design so this shouldn't change anything, image-wise. This makes the lens successfully focus at a distance of about 12 feet. Ergo, I can use the lens as a fixed-focus lens as I intended. And if I want to really fool around, removing the set screw gives me a sliding lens that can be focused from far to close by guessing. I determined the aperture as f/8 so the DOF is somewhat large enough for mostly guessed focusing, though I could potentially experiment with marking the barrel.

Why all the trouble? Well it's fun to tinker sometimes. Testing the lens on my Leica M9 (with adapter of course) shows it is pretty dang sharp and has character. It's also tiny and can technically focus closer using the sliding technique above than any other traditional lens I have, short of free-lensing. I paid practically nothing for it, so why not?
 
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