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Re: Enlarger lens

Started by Walter, 05/31/2002 06:25PM
Posted 05/31/2002 06:25PM Opening Post
In the case of an enlarger lens, the listed f is the focal length, the f/number is the speed, ie f/4.5, so the approximate aperature would be 164/4.5 = 36.4mm. It really wouldn't make a very good telescope, but a useful small finder maybe.