ZI Pro Tessar Balsam (OT)

[hugivza]

I recently bought 35/4, 85/4, and 115/4 Pro Tessars. The 35 and 115 exhibit a balsam problem, which in the case of the 35 mm is quite bad, covering 2/3 of the optic (it looks like a splodgy newtonian ring). The 85 has an annular problem on the rear couplet about 3 mm wide around the periphery. I understand that Zeiss changed balsam suppliers at some time in the early 60's and the problem is fairly common. I cannot grizzle as I only paid $US 20 for the 35mm lens. Does anyone know if it can be fixed reasonably(I do not have to mortgage the house, sell the car etc), or is it the kiss of death? I have shot some B and W film with all three lenses and am waiting to develop them this weekend to see if the results are significantly affected.

 

[RObert Budding]

There is another option - I have a Contaflex Super B and the 35/3.2, 50/2.8, 85/3.2, and 115/4.0 lenses in perfect condition (nice coatings and no fungus or separated elements) and I'm planning to sell them. The camera was CLA'd by WW Umbach and it works perfectly - everything moves nicely and the shutter speeds are accurate. Even the meter works. i just have too many cameras.

Robert

 

[Sonnar Brian]

I bought a Canon 135mm F3.5 lens in LTM for $21 that was described with extreme coating damage. It turned out to be the balsam that cemented the 2/3 elements into a group. Not wanting to spend anything on it, and not wanting to heat the old glass to over 300degrees to fix it, I used the "Cheese-Wiz" solution. I took the elements apart, used alchohol to remove the balsam, and used index matching oil as a replacement. Once the pair went back into the fixture -which was quite tight-, the oil flowed and Newton Rings went away. Surface tension between the mated surfaces is enough to hold them together. More than a year later, the lens is fine.

"Cheese-Wiz" fixed lens, wide-Open on the Canon 7:

http://www.rangefinderforum.com/photopost/showphoto.php?photo=2346&cat=3204&page=2

 

[hugivza]

Robert, I'd love to think about it, it could be a short way to an easy death when the wife says "you've done what?!" I have increased my camera collection some during the past year (5 in fact) and there is nothing like a good adrenaline rush. Are you selling it as a package or will you split the lenses and the camera?

 

[hugivza]

Thanks Brian - I'll save the post and give it a go as my investment is not such that I have too much at risk.

 

[RObert Budding]

It took me a while to assemble the kit - it would be nice to sell the entire kit, but it isn't required.

I, too, purchased a few "mint" lenses that had very bad separation problems. Because of those experiences, I now never buy from anyone who professes ignorance of cameras.

Robert

 

[Kin Lau]

Resurrecting this thread a bit, anyone know how to disassemble the 35/3.2 Pro-Tessar? There's no screws anywhere, and there's no notches in the front for a lense spanner. I'm guessing that I'll be using friction on the front ring.

 

[Mike Kovacs]

Well recementing the lens is not going to be cheap. John at Focal Point quoted me $300 to recement the triplet in a Zeiss Sonnar in Contax RF mount.

The issue is that Zeiss didn't use balsam at all, rather a synthetic type of epoxy. I don't quite follow your description - is this separation all starting at the edges, with a rainbow type pattern? I have fixed lenses with this problem by "filling-in" the separation with transparent oil, held by capillary action. It requires complete disassembly of the lens and the glass must also be free of their metal mounts, if applicable. The Sonnar mentioned above has held-up almost a year now with no change, and was used to make many of my gallery posts here.

 

[hugivza]

"Well recementing the lens is not going to be cheap. John at Focal Point quoted me $300 to recement the triplet in a Zeiss Sonnar in Contax RF mount".

Henry Scherer suggested a price significantly less than that for fixing up my two Pro Tessars. It would be worth contacting him. I have decided to wait pro tem as I have just received Bob Budding's Super B and Pro Tessars which are immaculate. If I recall Henry's comment, he suggested that Zeiss had used both epoxy and balsam for the Pro Tessars. The deterioration with the balsam results in the sort of problem which is on my lens (Check out my gallery I have posted a couple of shots of the 35/4 and the 115/4 as I cannot work out how to attach them to this post!) Surprisingly, the newtonian rings on the first couplet have not made any noticeable deterioration in image quality (could be my eyes!). The 115 is showing an annular separation on the rear element (the half moon shape in the photo). Conversely, the epoxy problem is evidenced apparently as bubbles.

Good luck!

 

[hugivza]

OK OK I worked it out all by myself - I have attached the photo of my 35/4 and 115/4 lenses showing the "balsam" problem. I will remove the ones from the Gallery

 

[RObert Budding]

Your 35mm looks like some of the "mint" lenses I bought off of eBay!

Robert

 

[Mike Kovacs]

That is the oil on water looking, epoxy type separation that Scherer does not repair.

 

[hugivza]

Thanks for the good news Mike!! At least the 35mm was only a $US20 "investment", and I have since, courtesy of the Forum, replaced them with a mint set of Pro Tessars. I have just run a film through using the 35/4, which is the worst cosmetically, and will compare it with the recently acquired 35/3.2 under similar conditions. My early assessment was that it seemed to make little difference to the image. Of course, that could infer that the images were lacking in any event.

 

[hugivza]

You might be interested to see the effect of the balsam shown in the 35/4 lens (left hand image in my earlier post) in comparison with a 'mint' lens. Both photographs were taken at around f8 (slower film would have helped to open the lens up). The photos, which were taken a week apart, were taken with different lenses on two different cameras. The first (LH image) is the 'balsamic/epoxy' lens 35/4 in a Contaflex IV. The second is the 'mint' lens 35/3.2 in a Contaflex Super B. Whereas one of the disadvantages of increasing age is diminution of visual acuity, I cannot see any marked difference in the images. My $20 may have been well spent after all, despite the cosmetic impact. Clearly, there will be some lighting conditions, perhaps wide open where the problem will affect the image.

 

[Mike Kovacs]

Compare the two at the widest f/stop where light is transmitted through the separated portion to the film.

I agree the effect is actually quite benign from my own experience. If you look in my gallery, the photo of Ally in the blanket was made with my Sonnar before I took care of the separation. Shot indoors, the aperture must have been around the f2-2.8 range.

 

[hugivza]

It hard to argue with success. It's a delightful image in any event. Incidentally, my Kiev 4 arrived on Friday so have been using it this weekend with the J3 I bought some time ago. It will be interesting to compare with the Sonnar.

 

[RObert Budding]

I just rummaged around and found a few more Contaflex accessories - I have a very fine 90 degree finder that makes tripod work very easy - you just peer down into the eyepiece from above. I also have a Contrapox close-up set and a few filters. Also have a polarizer.

Let me know if you are interested.

Robert

 

[RObert Budding]

One other thing - I wouldn't expect that the separation would be noticable at f/8. Try it wide open.

Robert

 

[RObert Budding]

Getting late - the closeup filters for the Cotaflex are "proxars," and there are 4 of them.

Robert

 

[Mike Kovacs]

I'm certain a properly cleaned and adjusted J-3 is as good as any prewar Sonnar. Versus my postwar Sonnar 501.5, its a tough call whether its better than a prewar design. Both are darned good optics! The postwar is a little nicer to use since it has a linear aperture scale.