Choosing A Lens By Calculation - Digital Projection TITAN sx+ 3D Dual 3D Ultra Contrast User Manual

2. Installation

Choosing a lens by calculation

For any screen size not listed above, or if you need to be more precise, then use the
calculations below.
• Identify actual width of the image in pixels.
• Calculate the Throw Ratio Factor:
• Identify the screen width required.
• Identify the throw distance required.
Throw distance calculations are based on the distance from the outer end of the
lens, which will vary from lens to lens. Once a lens has been chosen, the figures
can be checked using the lens extension values given on the next page.
• Calculate the throw ratio required.
• Choose a lens with the required throw ratio from the list at the bottom of the
page.
Check from the list that the lens chosen will work at the throw distance required.
Example
• An image, 1024 x 768 pixels, screen width 6.5m, throw distance 18m from the
outer end of the lens.
• Throw Ratio Factor (TRF) =
• Throw ratio required =
• Choose the 2.0 - 2.77 zoom lens (105-611).
0.73 : 1 fixed lens
1.2 : 1 fixed lens (3 - 15m)
1.2 : 1 fixed lens (1.2 - 2m)
1.26 - 1.61 : 1 zoom lens
1.5 - 2.02 : 1 zoom lens
2.02 - 2.77 : 1 zoom lens
2.77 - 4.51 : 1 zoom lens
4.51 - 7.53 : 1 zoom lens
7.5 - 11.2 : 1 zoom lens
Page 2.8
Digital Projection
TRF =
Throw ratio =
1400 = 1.37
1024
18 = 2.02
6.5 x 1.37
High Brightness
105-607
105-608
105-609
109 236
105-610
105-611
105-612
105-613
109-235
TITAN sx+ 3D, Dual 3D, Ultra Contrast
DMD width (1400)
Image width in pixels
Throw distance
Screen width x TRF
High Contrast
107-195
105-608
105-609
109-359
107-196
107-197
107-198
107-199
109-358
Notes
The Throw ratio for a particular
lens is fixed, and assumes that
the image fills the width of the
DMD.
For images that do not fill the
width of the DMD, the Throw
ratio is effectively increased. To
correct for this, a Throw Ratio
Factor (TRF) is used.
Throw distance range
1.1 - 3.2m (3.6 - 10.5ft)
3 - 15m (9.8 - 49.2ft)
1.2 - 2m (3.9 - 6.6ft)
3 - 15m (9.8 - 49.2ft)
4 - 24m (13.1 - 78.7ft)
4 - 24m (13.1 - 78.7ft)
9.1 - 45m (29.9 - 147.6ft)
12 - 80m (39.4 - 262.5ft)
12 - 80m (39.4 - 262.5ft)
Rev A August 2009
User Manual