Calculate Throw Distance And Position - Christie Matrix StIM-WQ User Manual

Setup Procedures

Calculate Throw Distance and Position

Throw distance is the distance measured from your projector to the screen. This calculation
determines if there is enough room to install your projector with a desired screen size and if the
image size will be the accurate size for your screen. To estimate the throw distance take the
horizontal width of the screen and multiply it by the lens throw ratio. The result determines
approximately the distance the projector should be positioned from the screen to project a focused
image large enough to fill the screen. For example, using a 1.28 - 1.71 zoom lens set at its widest
(1.2:1) throw ratio, throw distance would roughly be 1.2 x screen width.
Use the lens and screen size to calculate the precise throw distance. Due to lens
manufacturing tolerances for lens focal length, actual throw distance can vary ±2% between
lenses with the same nominal throw ratio.
Lens Throw Offset Percentage
Distance (Offset Pixels)
Horizontal
1
left
0.68:1 ±10%
1.28 – 1.71:1 60%
0.80:1 60%
1.The left and right horizontal offset examples are based on the projector being in the normal landscape orientation and
looking towards the front of the projector from the back (input panel side).
1. Offsets are subject to ±7% centering tolerance.
2. Image size outside the specified width range may result in reduced image quality.
3. Throw distance is measured from the marked exit pupil position on the lens to the
screen. Throw ratio is defined as:
4. 100% offset is defined as having all pixels shifted beyond the projector optical axis.
5. Offsets are measured from the optical lens centre, which may not coincide with the
mechanical centre.% offset is defined as:
10
Vertical
up down
1
right
±25%
-85% 140% -110%
-85% 140% -110%
Throw ratio = throw distance ± 2%
% Offset = # of pixels of offset
half vertical panel resolution
Specified Throw Distance Range
Inches
Min. Max.
28 83
59 213
28 102
screen width
x 100
Matrix StIM™ WQ/SIM WQ User Manual
Meters
Min. Max.
0.7 2.1
1.5 5.4
0.7 2.6
020-100883-01 Rev. 2 (06-2013)