Epson ELPMB28 Guide D'installation page 15

Distance from projection surface to wall plate
The distance (c) from the projection surface to the wall plate is the number given when the vertical slide is set
to the base position, as shown below.
Match the notch on the wall mount to the position of the stamp on the wall plate.
The measurements may differ depending on the location where you place the
projector.
When projecting in Tele, the quality of the projected images may decrease.
When using BrightLink Pro 1410Wi, BrightLink 475Wi/485Wi, or PowerLite 475W/
485W to project images at a 4:3 aspect ratio, the images are resized automatically and
the quality of the projected images may decrease.
Base position
Stamp on plate
Notch on mount arm
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