Auteur: Dan Fromm
Date: 15-12-2005 23:18
Philippe, pardonnez mon anglais, SVP. Je me suis leve ce matin a 0300, maintenant c'est 1640, et je suis tre fatigue. Je ne puis ecrire plus en francais.
Big Betax shutters are not very expensive. Mounting a lens in front of one requires an adapter to hold the lens, as in the eBay listing.
The least expensive Copal #1 Press shutters are from the Polaroid MP-4 camera. They have no diaphragm and a shutter open/close lever for focusing. I have two. If I wanted another I'd bid $50 on eBay until I got one. $40 and more patience should also get one.
The adapter that holds my 305/9 Apo Nikkor in front of a Copal 1 cost $135 from SKGrimes. There may be a less expensive way to hold a lens in front of a shutter, and there may be -- I hope there is -- a less expensive machine shop in France.
The important thing for you is that the MP-4 shutter's aperture is 30 mm in diameter. The radius that the lens must cover with no movements on 4x5 is 75 mm. By similar triangles, the distance from the lens' exit pupil to the shutter's aperture cannot be more than 25% of the distance from the aperture to the film if the lens is to cover 4x5. That is, at infinity the exit pupil can't be more than f/5 from the shutter's aperture. I think the 305 will satisfy this condition easily. The 210 may work, but is a little tight. And note that since the two lenses have different sized mounting threads you'll need an adapter for each.
There is a reason why used repro lenses sell for so little and why not everyone uses them. Buying one and putting it to use can cost more than a used modern lens in shutter. Repro lenses that go easily into a shutter, e.g., G-Clarons, sell for much more than equivalent lenses that will not go into a shutter without extensive machining.
Americans who use lenses in barrel with a Packard shutter have told me many times that the best way to work with this equipment is to use slow film -- ISO 25, ideally -- and small apertures. They say that timing exposures of several seconds duration is very easy. I don't see how one can avoid the need for shorter exposures. They say that with practice exposures in the range 1/25 - 1/5 can be obtained with a Packard. Also that I lack imagination and the right kind of experience. This is true.
Bonne chance,
Dan
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