Polaroid 636 Repair Manual page 32

27. For NEAR subjects the logic instructs the clock to stop the exposure at 124 ms after the
blades open. For FAR subjects the clock will time-out at 396 ms to stop the exposure.
28. However, the ending of the exposure is also subject to the photocell light measurement. In
other words, for a Low Ambient NEAR or FAR picture, there is still a race between the
photocell and the clock to shut down the flash and close the blades.
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