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Author Topic: Oil between elements in anamorphic lens Luciano Brigite Master Film Handler Posts: 277 From: Sao Paulo, SP, Brazil Registered: Jan 2002 posted 10-19-2002 06:21 PM                     I have an anamorphic lens that was out of use for several years (read here at least some 10 years or more), it's a PZO-Warszawa NA32 anamorphic lens and after taking it out of all the paper/plastic wrapping and de-assembling it for cleaning, I noticed that there is a rainbow-like reflection in the front elements block when viewing it under light. this block has 3 elements placed together and I beleive, cemented together. with all the time without use, the grease used around the collar and inside the lens tube ( to prevent locking while adjusting) melted or something and the oil from it leaked everywhere , outside and inside the tube and got between the elements . I tested it with a commom light bulb and a piece of cardboard with a piece of scope film placed in front of a oppening in the card, it didn't show any noticeably interference with the image but I'm afraid that with a brighter light ( like xenon) it will put out some interference ( chromatic aberration ?) in the image on screen. The problem is.. how to clean it out without separate the elements ( I think they can't be separated) Any idea, help, hint about what can be done to clean it out or how to separate the elements for cleaning? Thanks!  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-19-2002 09:19 PM                     Anamorphic lenses can only be disassembled, cleaned, reassembled, then re-aligned properly by the manufacturer of the lens. All elements must be true to each other to withina minute tolerance to work well. You will have to return it to the original manufacturers repair facility if they have one. Mark @ CLACO  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 10-19-2002 09:40 PM                     Mark is absolutely correct. However, it might be cheaper to get a good used lens instead of fooling around getting yours rebuilt.  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 10-20-2002 01:16 AM                    True to a degree I suppose but if you are dealing with simple lens consisting of two cemented doublets it could be aligned while projecting (under low intensity of course) a single frame of 35PA/RP40. The trick is to not have the element doublet shift while tightening. But don't even consider trying it unless the lens is beyond use and/or you were going to replace it or have it professionally repaired if your efforts failed anyway. Because it's just as likely you'll do more harm than good.  |  IP: Logged Luciano Brigite Master Film Handler Posts: 277 From: Sao Paulo, SP, Brazil Registered: Jan 2002 posted 10-20-2002 08:11 AM                     Oh well.. I think it's better throw it away then. I did this kind of cleaning work before with a few anamorphics but all of them ( 4 lens) had only 2 elements, one in the front and another in the back of the tube. aligned them with the test film Steve said. But this one is a bit different, it has a total of 5 elements, 2 in the back and 3 in the front. the problem is with the 3 elements block where the oil got between two of them . It also has some minor scratchs due to cleaning with the wrong stuff . Even the cheap, used lens is a bit expensive for me right now and I don't think that replacing only one lens with another of different kind ( manufaturer, model and so on) is a good idea then I'd go for a new pair ,but not for a while. Will keep trying on this one.. if I ruin it, no big loss. at least I learned ( I think) a little more Thanks  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-20-2002 07:10 PM                     The elements could be seperated by a professional optician that knows how to do so. The big but in repairing this lens is aligning the elements when they are cemented back together. In the shop, or lab this is almost always done with a special optical adhesive that cures by exposure to ultraviolet light. This gives alot of time to get the pair aligned before curing the adhesive. Its all in the alignment on anamorphics. The accuracy needed is so great that about the only places that can do it are the factories that made them. Mark @ CLACO  |  IP: Logged Sam Hunter Jedi Master Film Handler Posts: 779 From: West Monroe, LA, USA Registered: Jan 2002 posted 10-20-2002 08:05 PM                     If you want a cheap lens try ICECO. They made me a good deal on a couple of B-L's. Hey guys, its a start. Also you can check with Jon Bajon Jon Bajon, Inc. Jon Bajon, President 2611 North Dumont Baton Rouge LA 70814 (225) 275-9914 (225) 272-3841 Anyway good luck.  |  IP: Logged Luciano Brigite Master Film Handler Posts: 277 From: Sao Paulo, SP, Brazil Registered: Jan 2002 posted 10-20-2002 10:02 PM                     Oh well, I think I'll leave the lens as is and try to use it while I look for a pair of same kind , already talked to a few people and I'm waiting for their answer. I'm on a very tight budget right now because I'm rebuilding both projectors and had to get several new parts for it ,to make it better.. the theatre I was working at closed doors forever and I got kicked out ,started working again last week then not enough $ to get new stuff for now. I was thinking about getting new lens ( anamorphic, primes and flats) but I'm not in the US then the current exchange rate of about 4:1 makes it a no-no for me ( $4 in my currency is $1 USD ) Thanks for the advices .  |  IP: Logged

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