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View Full Version : Help! Lens de-cementing experiences



Nick Morris
25-Jun-2004, 12:04
Hello, I just received a lens I bought on eBay. I was surprised and pleased to find it was a "Production Standard Quality Control" lens, but found that it has what may be a serious problem. It looks as if you are looking into an eye when you look into the front component of the lens with the shutter closed. There is a dark circle about a 1/2" in diameter just off center, surrounded by a lighter, mis-shapen circle. When looking through the lens, into the light, with the shutter open, these circles are faint, but visible. They appear to be below the surface of the glass. Several people I've discussed this with (they haven't seen the lens) have suggested that it may be that the elements have de-cemented. The lens is a 13" Wollensak Series 1A Raptar for my 8x10, which has 4 elements in the front component. It appears that this de-cementing, if that is the problem, may have affected two of the elements in the group. I have put the lens on the camera, and the image on the GG looked good, but I have been told the problem may transfer to the film. Of course, the best way to know if and to what extent the problem will manifest on the film is to test, which I will do. However, I am interested to know if anyone has had this type of situation? Did it have an affect on picture quality? Is it a condition that gets worse? Any information would be helpful. I'm not particulary afraid of less than pristine lenses. I have had some very good results with some pretty crappy lenses, but those results can not always be relied on with a bad lens. Again, any information and experience shared is appreciated. Thank you.

Deniz
25-Jun-2004, 12:29
not exactly like your problem, but i have an older B&L lens that is seperating on the edges of the both front and back element, it is a big seperation and is visible even in total darkness :)

I haven't had a problem with soft corners in my images with this lens.. it has a big coverage and i stop down to f45 anyways so i never experienced a quality loss.

cheers

ronald moravec
25-Jun-2004, 12:48
Had a Wolly 210 pro raptar that decemented. Paid for repair. Then the shutte broke. Paid for repair. Then it decemented again! It was replaced with a G Claron 210 f9 and it a much better lens. I have replaced all the old ones

Nick Morris
25-Jun-2004, 16:48
Ron, thank you for your reply. Who made the repair, re-cemented it, and how much did they charge? Did you use your lens when the cells were de-cemented, and what difference was there in the performance? Thank you. Nick

Colin Carron
26-Jun-2004, 19:55
Nick,

I had an old Schneider Angulon where an element decemented itself. First thing I knew was the shutter jamming as the loose element got stuck in the works. The shot taken just before it fell apart looks ok by elderly Angulon standards. So as long as you can live with less than razor sharp results it may well not be a major problem. Repairers were not keen to take on the Angulon so I tried recementing with a Glass Bond adhesive designed to do exactly as it says. It is UV sensitive so you have to work in low light to align the elements then expose to sunlight. It worked ok though I got a newer Angulon to replace it as they are so relatively cheap.

ronald moravec
27-Jun-2004, 02:10
it was my first large format and it was a borrowed Kodal 5x7 and I used to center a 4x5 in the 5x7 holder. Talk about makeshift! Mine was an all over decementing, not confined to a small area. International Camera fixed the lens and the shutter. A a matter of fact, they screwed up every repair I ever gave them. They are in downtown Chicago now. I no longer give them work.

ronald moravec
27-Jun-2004, 02:13
yes - recementing improved things very much, it just didn`t last more than a year and taking out the three trips to get the shutter fixed, it never got much use.

Nick Morris
29-Jun-2004, 19:00
I thank you all for your help. I spoke with John at Focal Point in Colorado. He said it sounded like decementing, but that he would have to see it. Being that the front group, which has the problem, is comprised of four elements, the cost of the repair will likely be over $300, plus shipping. I shot with the lens, and the results were very, very good. At first, on one shot I thought I had serious flair, but after looking at the negative a little longer I realized that the behind-the-lens filter frame slipped into the path of the image. A long story, but certainly a "problem" that can be corrected. I made negatives at apertures of 8 1/2, 11 1/2, 32 1/2, and 45; and all looked good. Excellent shadow detail, and very sharp. Results were superior to negatives made with my 9 1/2" Dagor, which is a very good lens. I plan to keep the lens. At what point I have it repaired, I don't know. I guess I'll keeping shooting with it until it shows a problem on the film.