Runco cl-410 User Guide

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Runco CL-410 and CL-420 Owner’s Operating Manual
Vertical and Horizontal 
Position
Proper placement of the projector relative to the screen will yield a rectangular, 
perfectly-centered image that completely fills the screen. 
Ideally, the projector should be positioned perpendicular to the screen and in such a way 
that the lens center and screen center are aligned with each other, as shown in Figure 3-3. 
Figure 3-3. Projector Placement
Vertical and Horizontal 
Lens Shift
If it is not possible to align the projector and screen as shown in Figure 3-3, you can use 
the lens shift controls to center the image on the screen. Lens shift is generally expressed 
as a percentage of the screen height or width, as shown in Figure 3-4 anFigure 3-5. 
Figure 3-4. Vertical Lens Shift (Example only)
Height
Projection Distance
Ceiling
Ceiling Installation
Screen
Height 
Floor
Lens Center
Projection Distance
Floor Installation
Lens Center
x
Lens Center
x
Screen
Lens Center
Base plate
to lens center =
approx. 4" (depending
on the amount of lens shift)
50% Height
Lens Shift 
(0.5 x H)
100% Height
Lens Shift
(1.0 x H)
150% Height
Lens Shift
(1.5 x H)
Screen Center
0%
Note: This is a general example of lens shift. Lenses vary in their shift capabilities. No particular 
lens or projector is shown in this example.