Bill,
it is inside a copal 3 shutter and I created my own f marks by measuring light with a special light meter. So that would not be a problem.

That is a very nice page you found for me. Thanks!

I am going to take portraits of windmill operators here in my province in there mill and eventually want to make a book out of it.
My wife is also a mill operator, so it's a little step towards thats....