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View Full Version : What is this, separation?


patrickjames
9-Dec-2007, 15:03
This is a Symmar 135mm. I think this is separation, probably caused by an impact, but I am looking for confirmation. I was also wondering if it is fixable and what kind of cement Schneider used to cement it. Balsam? Something else? Any info you guys could give would be welcome. Here's a pic of the offending part. It looks to be between the two last elements.

http://www.patrickrobertjames.com/rff/CRW_9227.jpg


Patrick
Patrik Roseen
9-Dec-2007, 15:21
Hmm, I have seen this 'snowflake pattern' on lenses with fungus...bad examples can have lots of them.
Greg Lockrey
9-Dec-2007, 15:36
That's fungus alright.:(
Ole Tjugen
9-Dec-2007, 16:03
Looks like separation to me - a devitrification of the cement. fungus would be on the surface of the glass, separation and cement failure between the cemented components.
Frank Petronio
9-Dec-2007, 16:10
it's kinda pretty though

Focal Point can recement it but it would cost $180 or so. Just buy another 135 on eBay and keep the best shutter, eBay the other shutter. You might even break even!
erie patsellis
9-Dec-2007, 16:11
Patrick
I have a 360 Componon with the same issues on both front and rear elements, it's seperation, shoot with it, you really won't see it in the final image. The only time I see it (and only from the rear element) is if I have an out of focus point of light, it shows in the blurred disk, you'd have to know it's there to ever see it, in fact.


erie patsellis
Jim Galli
9-Dec-2007, 16:16
Squash blossom. Renders your lens worthless for anything except taking pictures. It won't affect your pictures at all.
patrickjames
9-Dec-2007, 16:23
Does anyone know about the cement type? I know you can cook balsam in the oven to help with the separation, and I have balsam to replace it. I have done this before. I am just wondering if the cement is synthetic. It is a Symmar convertible if that helps with the age of it. According to Schneider's lens list it is from 1963. Any opinions?

Patrick
erie patsellis
9-Dec-2007, 16:26
Patrick,
seriously, unless you bought it strictly to sell it, go shoot it, the only thing it really affects is price on the used market.


erie
Glenn Thoreson
9-Dec-2007, 18:01
Trying to take one of those apart and get it cemented back properly is a risky business. You could wind up with something totally unusable. If you do decide to persue this, I would soak it apart in acetone or lacquer thinner. If it has balsam cement, it will slide apart after a lengthy soak.
Heating it could break it. I say, just use it, as is.
Kevin Crisp
9-Dec-2007, 18:18
The shiny snowflake on this generation Symmar is separation. It happens. I had one with three of those and it took great pictures. Don't worry about it. This is held together with a post-balsam more modern cement. They are a bear to take apart, it involves a solvent (see Summers Optical website) and a hotplate/burner and some luck. It might come apart with months of soaking in MEK, but maybe not. Then you would have to learn the technique of recementing lenses which takes some time and, unfortunately, some errors. Unless your time is worth absolutely nothing to you, and you want to spend a bunch of it making a repair to something that isn't broken, with an eye toward having a "fixed" result that is probably worse than what you have now, go take pictures with it. Not that I intend to discourage you or anything...
Jim Galli
9-Dec-2007, 18:19
Glenn is right. I had a similar Rodenstock 210 that I soaked for 6 weeks in acetone. Finally I gave up on the acetone just earlier today and applied some heat. POP. It's in the trash can now. Canada Balsam was easy. I won't mess with a modern lens again.
Bryan Lemasters
9-Dec-2007, 18:22
I have to agree with Jim. Never knew what it was called but I had an early 90/f8 Super Angulon that had several of these inside both the front and rear elements. Looked awful, but my transparencies always came out fine.:confused:
patrickjames
9-Dec-2007, 18:36
If it was balsam I would take it apart, but since you guys think it is not, it isn't worth the time or effort to do it. I will test it out and see if I have any problems with it. My only concern is flare. I wish this was in the front elements, them I wouldn't even be concerned.

Patrick
Alex Wei
9-Dec-2007, 20:31
If you want to try to take it apart, methylene chloride can help to dissolve the modern cement.

Alex W.

PS. One has to be careful with this chemical, potential carcinogen.