
Positioning the Projector
65
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 be changed by rotating the zoom ring; see
page 69 for more information.)
Standard Lens Calculations
To determine the maximum and minimum diagonal size of an image
when you know the projection distance:
❐ Inches:
Maximum diagonal size = (0.676 × projection distance) + 2.293
Minimum diagonal size = (0.483 × projection distance) + 1.639
❐ Centimeters :
Maximum diagonal size = (1.71 × projection distance) + 5.824
Minimum diagonal size = (1.22 × projection distance) + 4.163
To determine the projection distance when you know the diagonal size
of the screen image:
❐ Inches:
Maximum projection distance = (2.070 × diagonal size) - 3.393
Minimum projection distance = (1.480 × diagonal size) - 3.393
❐ Centimeters:
Maximum projection distance = (5.257 × diagonal size) - 8.6182
Minimum projection distance = (3.759 × diagonal size) - 8.6182
80009000.book Page 65 Monday, November 1, 1999 9:35 AM