| Use a piece of focusing screen, matte side face down, place it between the
two outer film guide rails. Mount the camera on tripod, remove the camera back, with a 50mm macro, 85mm or 100mm tele,
focusing downward (best close to min. focusing distance) on sharp
printed book or newspaper, set the camera to "B", with a shutter release
for locking the shutter.
First, focus through the finder on a character (best using matte area for focusing), mark the focus point on the lens (you may stick a tape on the focusing ring, then mark with a ball pen on the tape). Trigger the shutter, with a 10x lupe, check the focus on the focusing screen which placed at the film guide rails. Focus the lens on the same character again, check if the previous marked point is line up or not. |
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| Repeat the above procedure two or three times to complete the checking.
In case there is error you can try to stick a small pieces of tape under the mirror to correct
the errors. Tape position should be corresponding to the mirror rest pin position.
Be careful! don't touch the shutter curtain especially for non-cloth shutters. |
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