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David Gardner
29-Jan-2001, 16:00
This may be the mother of all beginner questions, but I've seached all over this site, and having found the answers to almost every other questions I've had, I haven't found the answer to this one. In short, how does one know if a given len s will work with a given shutter? I have to believe that these things come in di fferent sizes and/or capabilities, but I have yet to see an ad that says anythin g like "Barrel lens X, for use with shutter Y." Or is the answer that any compet ent machinist can make any lense work with any shutter?

Thanks in advance David Gardner

Steve Grimes.
29-Jan-2001, 16:56
There's no hard and fast rules about this. Most barrel lenses need to have modifications done and/or adapters made to fit into shutters. A good rule of thumb is that the iris diameter of the shutter must be as large or larger than the iris diameter of the original lens barrel.

See: http://www.skgrimes.com/lensmount/index.htm for a page about lens remounting in general. See: http://www.skgrimes.com/fits/index.htm for a page with a table showing an anecdotal list of various lenses fitted to shutters based on my experience doing this.

SKG

Geoffrey_1456
29-Jan-2001, 19:10
David,

Steve's lens table will give you a pretty good idea which shutter you should use for your barrel lens x. If you don't find you lens in that table, then the next thing you might want to consider is that: 1. unscrew both the front and rear lens units off the barrel of your lens x, 2. measure the threads, 3. compare with shutter mount specs, 4. Call Steve to confirm which shutter to use (so you have some numbers to talk about). He is the greatest!

Matt_1193
30-Jan-2001, 01:56
Steve,

How did the BJ standard work out?

One exception to the "most need adjustment" statement, is that many lens manufacturers now make the lenses to fit directly into Copals or other shutters. I have a brilliant Congo commercial 180mm, that threads directly into a Copal #3 (56mm) without modification or spacers. Now I just have to find a Copal # 3(s) that I can afford!