Christie roadie 25k User Manual page 19

INSTALLATION AND SETUP
when displaying at less than the minimum size (see 3.7, Adjusting the Image). If
images remain keystoned or exhibit uneven brightness, the projector may simply be
too high or low in relation to the screen. Relocate for optimized performance.
THE HORIZONTAL POSITION
of the image can
be manually offset—that is, shifted left or right
of lens center—by using the horizontal offset
knob on the lens mount. Starting with no offset,
the 2048 x 1080 image from this projector can
be moved by a distance of 410 pixels, resulting
in up to 70% of the image displayed on one side
of lens center (Figure 2.14).
Note that the positioning shown at right is often
mistakenly referenced as "70% offset" but it is
not—it is 40% offset derived as 410/1024 x
100. A 70% offset is explained below and
shown in Figure 2.15.
Figure 2.14. Horizontal Offset
Range
ALTERNATIVE METHOD OF DESCRIBING
HORIZONTAL OFFSET:
Horizontal offset
can also be specified as the distance
traveled from lens center and expressed as
a percentage of half of the image width.
For example, an offset spec of 70% means
a centered image can be moved by a
distance of 717 pixels, resulting in 85% of
the image projected to one side of lens
center and 15% on the other. See right.
NOTE: Example only. Beyond range for
this projector.
Figure 2.15. Alternative Offset
Specification
Floor Mounting
'
For front projection without suspending, mount the projector on a strong supporting
and Leveling
structure or cart. Take special care if using a mobile cart—avoid sudden stops, force
and uneven surfaces that may cause the top-heavy cart to lurch and overturn.
Make sure your mounting structure is reasonably level, then adjust one or more
projector feet as necessary to fine-tune.
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Roadie 25K User's Manual