Sony VPL-VW50 Operating Instructions Manual page 77

4
After you have decided the lens position, insert the Philips screwdriver
at the locations of the four screws around the border of the lens in turn
and tighten them to fix the lens in place.
5
Attach the ring (washer) by turning it clockwise.
Note
When you use the horizontal and vertical lens shift features at the same time and adjust the horizontal
lens shift to the maximum, the picture moves up to a maximum of 53% of its original position.
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