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Lensless Schmidt cameras

Started by Walter, 04/15/2002 06:15PM
Posted 04/15/2002 06:15PM Opening Post
MANY years ago I bought an 8" f/2 spherical mirror and film holder from Coulter Optical in CA. The idea was to make a lensless Schmidt camera by placing a field stop at the RC of about 5" in diameter. That, in conjunction with a curved film holder supported by a spider vane, was supposed to give relatively good astro images on 35mm film or 2" circle cut film. Well, I never actually put it together, and sold the set some time ago. Now, a friend has a 10" f/2.95 spherical primary that he wants to use for the same purpose. He is proposing a 7" aperature but projecting the image out to a camera body via a 3.1" diagonal. I'm leary??? Any knowledgable inputs/experiences out there?