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chrisg
Joined: 07 Jun 2010 Posts: 5
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Posted: Thu May 03, 2012 12:07 pm Post subject: Mistery lens: Carl Zeiss Jena Biometar 2,8/105 ! |
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chrisg wrote:
I have it. It is _not_ Biometar 80 nor Biometar 120 for medium format.
Google is unable to find anything about it. It does not appear in the 2009 Kadlubek catalog.
Do you know anything about this lens?
Description (I don't have the photos with me, but I will post them here later):
It's a lens apparently without the external shell. Somebody has made a custom optical unit externally combining this stripped? one and other lens.
There is no mount and no trace of a screw thread that could enable mounting it into some focusing assembly ending with the mount.
Its diameter is clearly less than of Biometar 120, so it doesn't look to be made for P6. It is about the diameter I would expect from a 35mm format FF longish 2.8 lens.
I've tried it freelensing style and it works, I can reach infinity as well with it 2..3 cm away from the camera mount.
Best is the aperture, it has the uncountable blades that give the round iris. It is placed between a front optical block and a rear optical block, so I would say the lens is complete but for some mounting/helicoid focusing mechanics.
Any clues? Ask your friends too |
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Pancolart
Joined: 04 Feb 2008 Posts: 3705 Location: Slovenia, EU
Expire: 2013-11-18
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Posted: Thu May 03, 2012 12:11 pm Post subject: |
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Pancolart wrote:
Great find. Sounds like enlarger lens but let the experts tell. _________________ ---------------------------------
The Peculiar Apparatus Of Victorian Steampunk Photography: 100+ Genuine Steampunk Camera Designs https://www.amazon.com/dp/B0B92829NS |
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calvin83
Joined: 12 Apr 2009 Posts: 7557 Location: Hong Kong
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Posted: Thu May 03, 2012 2:40 pm Post subject: |
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calvin83 wrote:
Some infos in an Taiwan blog http://blog.xuite.net/fdchen/lenses/22423280 . _________________ https://lensfever.com/
https://www.instagram.com/_lens_fever/
The best lens is the one you have with you. |
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chrisg
Joined: 07 Jun 2010 Posts: 5
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Posted: Fri May 04, 2012 9:42 am Post subject: |
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chrisg wrote:
Mine looks very similar, just that it has the inscription a front ring and nothing is written on the cylindrical body at the rear end.
As far as Chrome can translate the chinese there, the blog author also doesn't know much about it, just that it is a prototype.
I have made a helicoid mount for it from the body of a Pentacon 50/1.8 clone (Autorevuenon) and tried it.
At F4 is better than at F2.8 (estimated with the lighmeter in the camera, as there are no inscriptions for aperture) in terms of sharpness.
The bokeh is nice I would say (here at F4):
[/url] |
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Attila
Joined: 24 Feb 2007 Posts: 57865 Location: Hungary
Expire: 2025-11-18
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Posted: Fri May 04, 2012 10:02 am Post subject: |
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Attila wrote:
Enlarger lens _________________ -------------------------------
Items on sale on Ebay
Sony NEX-7 Carl Zeiss Planar 85mm f1.4, Minolta MD 35mm f1.8, Konica 135mm f2.5, Minolta MD 50mm f1.2, Minolta MD 250mm f5.6, Carl Zeiss Sonnar 180mm f2.8
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Fri May 04, 2012 2:00 pm Post subject: |
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iangreenhalgh1 wrote:
Isn't it more likely a barrel mount lens for large format? Why would an EL be coated? Also, 2.8 is fast for an EL, the Schneider 105mm Componon-S I have is f5. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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chrisg
Joined: 07 Jun 2010 Posts: 5
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Posted: Fri May 04, 2012 2:10 pm Post subject: |
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chrisg wrote:
iangreenhalgh1 wrote: |
Isn't it more likely a barrel mount lens for large format? Why would an EL be coated? Also, 2.8 is fast for an EL, the Schneider 105mm Componon-S I have is f5. |
I am by no means an expert in enlarger lenses, but indeed from what I've researched lately only the cine (projection?) lenses seem to be that fast (or even faster).
To me the lens looks too thin to be a large format lens (since it's obviously much thinner than my medium format Biometars, both 80 and 120mm ones). Now that I've made a temporary adaptation of it I had to measure, the rear barrel is about 42mm in diameter - but plain, without any thread. |
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ForenSeil
Joined: 15 Apr 2011 Posts: 2726 Location: Kiel, Germany.
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Posted: Sat May 05, 2012 10:40 pm Post subject: |
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ForenSeil wrote:
Most enlarger lenses are coated and some are fast so that's not a 100% cogent argument that it's not one.
Often especially bigger labs use fast lenses - when you have to make 500 or more prints per day some extra stops will be very usefull.
I think that it's not a projection lens as Carl Zeiss Jenar Projector lenses had very different dimensions and usually different names than their photo-taking counterparts (even with the same optics inside). But Zeiss Jena made also very large projectors for auditoriums (and lenses for them) - which might be another shoe, as it's very hard to find informations about them (they are rare because they were only made for Universities, "Palace of the Republic" or other larger public institutions of the GDR)
It might be also a photo-taking lens but I can't find any details to prove that.
Could you take a pic of the rear-side? _________________ I'm not a collector, I'm a tester
My camera: Sony A7+Zeiss Sonnar 55/1.8
Current favourite lenses (I have many more):
A few macro-Tominons, Samyang 12/2.8, Noritsu 50.7/9.5, Rodagon 105/5.6 on bellows, Samyang 135/2, Nikon ED 180/2.8, Leitz Elmar-R 250/4, Celestron C8 2000mm F10
Most wanted: Samyang 24/1.4, Samyang 35/1.4, Nikon 200/2 ED
My Blog: http://picturechemistry.own-blog.com/
(German language) |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Sun May 06, 2012 1:24 am Post subject: |
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iangreenhalgh1 wrote:
Projector lenses don't have apertures, or at least, I've never seen one with an aperture. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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chrisg
Joined: 07 Jun 2010 Posts: 5
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Posted: Tue May 08, 2012 5:50 pm Post subject: |
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chrisg wrote:
ForenSeil wrote: |
Most enlarger lenses are coated and some are fast so that's not a 100% cogent argument that it's not one.
Often especially bigger labs use fast lenses - when you have to make 500 or more prints per day some extra stops will be very usefull.
I think that it's not a projection lens as Carl Zeiss Jenar Projector lenses had very different dimensions and usually different names than their photo-taking counterparts (even with the same optics inside). But Zeiss Jena made also very large projectors for auditoriums (and lenses for them) - which might be another shoe, as it's very hard to find informations about them (they are rare because they were only made for Universities, "Palace of the Republic" or other larger public institutions of the GDR)
It might be also a photo-taking lens but I can't find any details to prove that.
Could you take a pic of the rear-side? |
Sure, here it is. The crenellated ring can be rotated and controls the aperture.
It took me some time to do it, as I had non-destructively arranged it for use, complete with focusing and shade (true franken lens with parts from others):
The filter diameter seems to be 46 mm (I don't know to include the screw depth). As said, the diameter of the tube on the back side is 42mm. I have counted also the blades, there are 15.
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