Calculating Image Size And Projection Distance - Epson PowerLite 5500C User Manual

When projecting from the ceiling, align the lens as closely as
possible with the top of your screen:

Calculating Image Size and Projection Distance

The distance between the projector and the screen determines the
actual image size. To determine the exact distance required for a
particular image size (or to determine the size of an image at a
particular distance), use the formulas given below. (Remember that
the size of the image can also be changed by rotating the zoom ring;
see page 47 for more information.)
Positioning the Projector
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