Runco VIDEO XTREME VX-33I - Manual (Page 33)

Runco VX-33i Installation/Operation Manual 17
PRE
L
IMINAR
Y
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 is aligned with either the top or bottom edge of the screen area, and
centered horizontally. See Figure 3-2.
Figure 3-2. Projector Placement
Vertical and Horizontal
Lens Shift If it is not possible to align the projector and screen as shown in Figure 3-2, 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 3-3 and Figure 3-4.
Figure 3-3. Vertical Lens Shift (EXAMPLE ONLY)
Screen
Height
Projection Distance
Ceiling
x
Lens Center Lens Center
Ceiling Installation
Screen Height
Floor
Lens Center
Projection Distance
Floor Installation
Lens Center
x
Base plate
to lens center =
approx. 5-6" (depending
on the amount of lens shift)
50% Height
Lens Shift
(0.5 x H)
100% Height
Lens Shift
(1.0 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 used in this example.