BenQ CP220 User Manual
Page 19
Positioning your projector
13
How to determine the position of the projector for a given
screen size
1.
Select your screen size.
2.
Refer to the table and find the closest match to your screen size in the left columns
labelled '4:3 Screen Diagonal'. Using this value, look across this row to the right to find
the corresponding average distance from screen value in the column labelled 'Average'.
This is the projection distance.
3.
On that same row, look across to the right column and make note of the vertical Offset
value. This will determine the final vertical offset placement of the projector in
relation to the edge of the screen.
4.
The recommended position for the projector is aligned perpendicular to the
horizontal centre of the screen, at the distance from the screen determined in step 2
above, and offset by the value determined in step 3 above.
For example, if you are using a 120 inch screen, the average projection distance is 5018 mm
and with a vertical offset of 63 mm.
If you place the projector in a different position (to that recommended), you will have to tilt
it down or up to center the image on the screen. In these situations, some image distortion
will occur. Use the Keystone function to correct the distortion. See
for details.
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.
Measure the distance between the projector and where you want to position the
screen. This is the projection distance.
2.
Refer to the table and find the closest match to your measurement in the average
distance from screen column labelled 'Average'. Check that your measured distance is
between the min and max distances listed on either side of the average distance value.
3.
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.
4.
On that same row, look across to the right column and make note of the vertical Offset
value. This will determine the final placement of the screen in relation to the
horizontal plane of the projector.
For example, if your measured projection distance was 4.8m (4800mm), the closest match in
the Average column is 4939mm. Looking across this row shows that a 3000mm (3m) screen
is required. If you can only obtain imperial sized screens, the listed screen sizes on either side
of the 3m screen are the 9' and 10' screen.
Checking the min and max projection distance values for these screen sizes indicates that the
4.8m measured projection distance will fit the 3m and 10' screens. The projector can be
adjusted (using the zoom control) to display on these different screen sizes at that projection
distance. Be aware that these different screens have different vertical offset values.