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View Full Version : Carl Zeiss Jena Tele-Tubus question - HELP



anton orlov
27-May-2014, 16:28
So, I was lucky enough to find a beautiful Tele-Tubus IV with a 225mm front single positive and -100mm rear lens (both by Zeiss). In literature that I found on Google books it appears that this particular combination was made for fast exposures when shooting 'large heads' and indeed it seems that the lens is super fast (somewhere about f3) BUT when I put it on my 8x10 I can not for the life of me get it to focus close on a person without racking out my bellows so far that the entire 'fastness' of it is pretty much void.

I understand that these lenses were supplied with a special chart for each positive/negative element combination. I have found a recent eBay sale for a PERFECT piece of literature about this, but alas it is gone. The name of that publication is "CARL ZEISS Jena 1896 Tele-Photographic Objectives USE OF TELEPHOTO LENS LENSES". Does anyone have anything like that? Any experience with Tele-Tubus lenses? Any help?

Very much appreciated.

Dan Fromm
27-May-2014, 17:23
This catalog http://books.google.com/books?id=cnkWAAAAYAAJ&dq=zeiss+unar&source=gbs_navlinks_s , which I have not read closely, has a discussion of the tele-positive, tele-negative and tele-tube. It may be what you want.

Tim Deming
27-May-2014, 22:50
I have some of these from other manufacturers. Generally, they allow you to use longer lenses at shorter bellows extension, typically at the cost of smaller effective f-stop. Usually you will put a complete lens on the front of the tele attachment. Sounds like you may have a single group of a protar VII on yours.

In your case, I'd worry that your combo will focus at a very short distance for an 8x10 camera. You might try it on a 4x5, or just focus the lens against a wall to estimate the effective focal length. It should be significantly less than 225mm at infinity

Cheers

Tim

anton orlov
28-May-2014, 16:44
Thanks Dan and Tim, I found that one before and indeed it was helpful. Now I actually found out that GEH has a copy of 1896 booklet that has the tables for focusing these lenses. It seems like the catalog advertised my combination of 225 Protar and -100 in the back as a 'fast portrait combo', but I still can't figure out how to get it focused close on a head without having the bellows racked WAY out. Well, I'll spend some time tonight messing around with it and see if I can decipher the catalog.

Dan Fromm
28-May-2014, 18:38
Anton, as I read the catalog your combination will make infinity with ~ 40 cm extension. Focusing closer will need more extension.

I imagine -- don't shoot 8x10 -- that an 8x10 head shot will be at roughly 1:1. If so, you need ~ 40 cm plus the combination's focal length. If I read the catalog correctly, its focal length is on the order of 80 cm. And there's the source of your extension problem.

Incidentally, there's no way 'round losing 2 stops of illumination at 1:1. That's the law.