Mystery Tessar 12cm

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

I thought that I was fairly good at researching this subject........but I cannot find ANY information on this CZJ Tessar 120mm. Serial number 1132296 suggests a 1930 build-year for this lens. It appears to have a brass body (plated with chrome or nickel) and a very firmly and professionally attached extension, which may or may not be aluminum. Extension mates perfectly to an M42 mount.

Lens was sent to me by eBay seller......along with an m42/Exakta adapter. I have been playing with lens on my Lumix GF2, using an Exakta/Micro 4/3 adapter that I had on hand. Will not focus to infinity with that combination. Wondering if a straight m42 to Micro 4/3 adapter will produce better results.

If I didn't know better, I would think that this lens was made for use on a Contax.....although I don't believe that Contax cameras came along until 1932.

Has anyone ever seen a lens like this???

ManualFocus-G · Expire: 2014-11-24

kds315* · Expire: 2021-03-09

Computed on 8.7.1913, made 19.10.1929 in a batch of 200 lenses, yours being no 96

Mos6502 · Joined: 20 Jun 2011 Posts: 960 Location: Austin

That is interesting. The same lens was available for the Kine Exakta, but of course that didn't exist yet in 1929/30. The VP Exaktas weren't built until 1932, so it's even too early for those. The length of the adapter does suggest the lens was originally used on something with a fairly large register distance like an Exakta VP, but I guess there's no real way of telling if they hacked any of the barrel off when adapting it without seeing it in person.

iangreenhalgh1 · Expire: 2014-01-07

Lens from a folding camera in a DIY tube mount?

Attila · Expire: 2025-11-18

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

Additional pictures of this Tessar. I have set focus on lens to nearest possible position. Notice slightly exposed helical and the line which is inscribed on aft area of lens body onto area which seems to be a bearing point against helix nearest to the objective....

kds315* · Expire: 2021-03-09

The focal length is 12cm = 120mm. Measure from lens head center to end of the tube (when lens is set to infinity), what do you get?

If you like to use it on a camera reaching infinity, you need about:

120mm - register length - half lens length (crude estimate)

where register length is also called "flange focal distance" as per http://en.wikipedia.org/wiki/Lens_mount,

so for Pentax M42 that would be:

45.5mm --->> 120mm - 45.5mm - half lens length = 74.5mm - half lens length

so assuming your lens head being 30mm long, half length would be 15mm, so

74.5mm - 15mm = 59.5mm tube length needed

to reach infinity. That could then be attached to a M42 adapter fitting your camera.

From your pictures it seems that this tube is a macro setup, not intended to reach infinity, so I would title it "Mystery Macro Tessar"!

(you would have to adjust figures as I am using assumptions here to illustrate)

More about that, estimating tube/focusing helicoids lengths is here on my BLOG:
http://photographyoftheinvisibleworld.blogspot.com/2011/01/how-to-determine-length-of-focusing.html

exaklaus · Expire: 2011-12-02

No DIY!
Here are some pics of my Tessar.
During the years, I had around 3 or 4 passing through my hands.
Obviously lenses from an overproduction at Zeiss or lenses, that were bought by Ihagee for cameras, that weren't produced.
Then, at the advent of the 35mm Kine Exakta, these lenses were probably given this focussing and the Kine mount at Zeiss or (what I believe) at Ihagee. They did the same with extra 2/8cm Biotars for the Exakta VP.

Klaus

kds315* · Expire: 2021-03-09

OK Klaus, this issue solved then. It seems someone has removed that mount and has added another short tube to it (first pictures shown of the OP) as also the knurled ring on the end looks different in style (more recent I'd say).

exaklaus · Expire: 2011-12-02

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

I am overwhelmed with other matters at the moment but will make measurements and reply this evening (Southern Illinois time).

Thank you very much for this excellent information!!!!!!!

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

kds315...........Thank you (and everyone else) for your replies.

Measurements of lens:

Overall length of lens including forward rim of filter mounting flange and outer aft rim of m42 mounting threads= 12.5cm

Approximate distance from center external surface of front element to end of body of lens minus threads and shank
of lens mount= 11cm

Approximate distance from forward outer rim of filter mounting flange to the "seam" which is visible in the side-view photograph of lens that is posted on this thread= 8.75cm (I am wondering if the Tessar 12cm owned by exaklaus might have a similar measurement between it's outer front and the rear of the main part of it's lens body, excluding it's Exakta mount....??????).

I am not sure how to measure the actual lens head that occupies the lens body......without taking the lens apart.....????

As an aside..........I have also experimented with this lens and my Lumix GF2........holding the mount of the lens directly against the Micro 4/3 mount of the camera. It seems to produce an image that is in focus. I am wondering if a very short-length m42 to Micro 4/3 adapter might produce a satisfactory result at infinity.......??? Please see attached experimental photograph.

Thank you for you attention to my questions. I find this lens to be of particular interest and your information has made it even more fascinating.

Attila · Expire: 2025-11-18

http://forum.mflenses.com/carl-zeiss-jena-tessar-12cm-f2-7-exakta-pre-war-t26340,highlight,%2Btessar.html

Here is mine.

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

I have been reading about the m42 mount......and noticed in the Wikipedia article on the subject.....that the M42 mount was first developed by Carl Zeiss at their Jena plant in 1938 at the request of the KW camera company for their Praktica line, which had previously used M40. It was only at this point that I remembered an old KW Praktica that I have had languishing in a drawer for a number of years.

I got out my old Praktica and put the 12cm Tessar on it. It seems to focus very sharply at a distance of a few meters from a subject. With the flange focal distance of 45.46mm on the Praktica's standard m42 mount vs. the Micro 4/3's flange focal distance of 19.25mm, I am wondering if the net difference in flange focal distance would allow a very short m42 to Micro 4/3 adapter to enable focusing to infinity on my Lumix......??????

I have attached a photograph of the 12cm Tessar on my old Praktica. I wonder if this lens was some sort of experimental attempt by Zeiss.....????

kds315* · Expire: 2021-03-09

I think you have to take apart the two tubes attached together and have the rear one (later added) shortened a bit, that should do for infinity then.

Maybe Attila or Klaus could give you the precises length it has to have (?) if you ask kindly enough Wink

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

Yes........That would be great.

The measurements that I asked Exaklaus to provide would also be very interesting.

I am going to order one of those short-length m42 adapters on eBay right now.

It will take a long time for them to arrive here.........but when I have the adapter, I will post the results.

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

I received an M42/C-mount adapter for my Micro 4/3rds Lumix. I attached this adapter to the "Mystery Tessar" and experimented with it this evening.

Lens does not focus to infinity (as expected) and seems to be suited to macro......but since lens is a long focal length, it is necessary to stand off quite a distance to be in focus.

I wish this lens could talk.....so that it might tell me what it was originally made to do. I plan to use it for floral photography next Spring.

One of my subjects for testing this "Mystery Tessar" tonight is the Christmas tree at my home. I will share these with you along with wishes for a Merry Christmas and a very happy and successful New Year....!!

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

I bought a regular M42 to Micro 4/3 adapter this week for use with another lens......Tried the lens that is the subject of this thread on this new adapter. Lens acts like a "telephoto-macro" with this adapter, as well. I took this image at a distance from camera to subject of approx. two meters....

I am wondering if this lens was made for some sort of industrial use.....?????

Ox Bird · Joined: 12 Dec 2013 Posts: 38 Location: Illinois

Springtime daffodils.........taken with the "Mystery Tessar" lens on a Panasonic Lumix GF2.

Not bad for a lens that will be 85 years old next October.