14 Positioning your projector
English
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 th e "Vertical offset in mm" 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 center 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 4416 mm and with a vertical
offset of 210 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 "Correcting keystone" on page 28 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 th e "Vertical offset in mm" 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 4.5 m (4500 mm), the closest match in the "Average"
column is 4416 mm. Looking across this row shows that a 120-inch screen is required. If you can only obtain
metric sized screens, the listed screen sizes on either side of the 120-inch screen are the 3.0 m (3000 mm) and 3.5
m (3500 mm) screens.
Checking the min and max projection distance values for these screen sizes indicates that the 4.5 m measured
projection distance will also fit the 3.0 m (3000 mm) size screen. Be aware that these different screens have
different vertical offset values.
There is 3% tolerance among these numbers due to optical component variations. BenQ recommends that
if you intend to permanently install the projector, you should physically test the projection size and
distance using the actual projector in situ before you permanently install it, so as to make allowance for
this projector's optical characteristics. This will help you determine the exact mounting position so that it
best suits your installation location.