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12
Important safety instructions
Obtaining a preferred projected image size
The distance from the projector lens to the screen, the zoom setting, and the video format each factors
in the projected image size.
The projector should always be placed horizontally level (like flat on a table), and positioned directly
perpendicular 90° right-angle square) to the screen. This prevents image distortion caused by angled
projections (or projecting onto angled surfaces). If the projector is mounted on a ceiling, it must be
mounted upside-down.
If the projector is positioned further away from the screen, the projected image size increases, and the
vertical offset also increases proportionately.
When determining the positions of the screen and projector, you will need to account for both the
projected image size and the vertical offset dimension, which are directly proportional to the projection
distance.
This projector is equipped with a movable lens. See
"Shifting the projection lens vertically" on page 16
for
details. You can see the diagrams on pages
for the vertical offset values in the dimension tables
that are measured when the lens is shifted fully up or down.
How to determine the position of the projector for a given screen size
1. Determine the aspect ratio of your screen, 16:9 or 4:3?
2. Refer to the table and find the closest match to your screen size in the left columns labelled
. Using this value, look across this row to the right to find the corresponding average
distance from screen value in the column labelled
. This is the projection distance.
3. Decide the exact position of your projector according to the position of your screen and the
adjustable lens shift range.
<Example>
If you are using a 120-inch, 4:3-aspect-ratio screen, please refer to
"The screen aspect ratio is 4:3 and the
. The average projection distance is 3207 mm.
How to determine the recommended screen size for a given distance
This method can be used for situations where you have purchased this projector and would like to know
what screen size will fit in your room.
The maximum screen size is limited by the physical space available in your room.
1. Determine the aspect ratio of your screen, 16:9 or 4:3?
2. Measure the distance between the projector and where you want to position the screen. This is the
projection distance.
3. Refer to the table and find the closest match to your measurement in the average distance from
screen column labelled
. Check that your measured distance is between the min. and max.
distances listed on either side of the average distance value.
4. Using this value, look across that row to the left to find the corresponding screen diagonal listed in
that row. That is the projected image size of the projector at that projection distance.
<Example>
If you have a 16:9-aspect-ratio screen and your measured projection distance was 4000 mm, please refer
to
"The screen aspect ratio is 16:9 and the projected picture is 16:9"
. The closest match in the
column is 4076 mm. Looking across this row shows that a 140-inch screen is required.
Checking the min. and max. projection distance values in the columns of
"Projection distance <D> [mm]"
indicates that the 4000 mm measured projection distance will also fit the 130 and 150-inch
size screens. The projector can be adjusted (using the zoom control) to display on these different screen
sizes at the projection distance. Be aware that these different screens have different vertical offset values.