Mounted a 15mm eyepiece lens from a spotting scope in a sheet of plywood fit to the back of my Super Speed Graphic. Racked the Graflex 1000 135mm Optar/Rodenstock lens out to get a sharp image in the eyepiece. The image was a 9X magnification. Pretty good image sharpness in the aerial image at the 135's focal plane with the lens wide open at f/4.5. Stopping down to f/16 through f/32 darkened the image but really sharpened it up to where I could see twice as many tree branches some 200 yards away.
Replaced the Graflex 1000 lens with a Graflex 90mm Optar f/6.8 W.A. I'm thinking about buying. It's image was 6X magnification. Again, wide open, it was nothing to shout about. Stopping it down to f/16 through f/32 showed it to be a little sharper than the 135.
The 90's Wollensak shutter's frozen but probably fixable. I may remove the front and back lens groups then put it in my ultrasonic cleaner with naptha to see if that helps. It's shutter speed dial is stiff and sluggish but the preview arm opens up and releases the shutter without problems.
Anybody ever tested lenses this way? Without the shutter working, I thought this would be a decent test as the telescope eyepiece is designed to focus sharpest at an aerial image at its focal length. Its 15mm focal length makes it a 16.7X loupe and the aerial image is clean, not grainy like ground glass images are.
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