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

Positioning the Projector

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