I'm confused.....I see some lenses mounted in Copal 1 shutters that have minimum iris openings of f64 and other lenses mounted in the same shutter that have some different minimum opening. Too confuse me further, I have a fairly new Copal 1 shutter (it has no iris scale)that appears to close down to about f45 or so. How can the same size shutter have different minimum iris openings ?
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