Digital Projection Titan 930, Руководство пользователя

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Digital Projection
M-Vision 930 Series
CHOOSING A LENS Reference Guide
86 Rev A January 2014
Full lens calculation example
Your screen is 3.5 m wide; you wish to place the projector
approximately 6.8 m from the screen. The source is 4:3 .
1. Calculate TRC as follows:
1.6
1.33
TRC = = 1.2
2. Calculate the throw ratio:
6.8
3.5 x 1.2
Throw ratio = = 1.62
3. Find a match in the lens table.
The table shows that the matching lens is
the 1.56 - 1.86 : 1
zoom lens .
4. Check whether the lens covers the required throw distance.
The range quoted for the 1.56 - 1.86 : 1 zoom lens is
2 - 7 m . The required distance of 6.8 m is within the range.
Notes
INFORMATION YOU NEED FOR THESE CALCULATIONS
•
The TRC formula
•
The TRC table (to use instead of the formula)
2.35:1 (Scope) TRC not used
1.85:1 (Flat) TRC not used
1.78:1 (16:9) TRC not used
1.66:1 (Vista) TRC not used
1.6:1 (16:10) TRC not used (native resolution)
1.33:1 (4:3)
TRC = 1.2
1.25:1 (5:4) TRC = 1.28
•
The throw ratio formula
•
The lens table:
Throw ratios Throw distance range
0.84 - 1.03 : 1 zoom lens 1.5 - 4 m (4.9 - 13.1 ft)
1.56 - 1.86 : 1 zoom lens 2 - 7 m (6.6 - 23 ft)
1.85 - 2.40 : 1 zoom lens 2.5 - 10 m (8.2 - 32.8 ft)
2.40 - 4.00 : 1 zoom lens 4 - 12 m (13.1 - 39.4 ft)
DMD™ aspect ratio
Source aspect ratio
TRC =
Throw distance
Screen width x TRC
Throw ratio =