What is Image Offset?
The image offset is the distance between the center of the lens to the image bottom (table top installation) or image top (ceiling installation). The image offset is typically greater than 100% because the projector has a fixed projection angle. The reason that we designed our projectors to shoot the image above the center of the lens is because the projected image will appear at a height that is practical for viewing. Otherwise, the projector would need to be at the same height as the center of your projection screen.
The image offset is presented as a percentage. The percentage is directly related to the image height. If you want to calculate the image offset, you would multiple the percentage by the projected image height. This calculation will tell you the estimated distance between the lens center and image bottom (table top installation) or image top (ceiling installation).
Example 1: 100% image offset |
Example 2: 125% image offset |
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Image top |
Image top |
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100% |
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image height |
100% |
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image height |
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Image bottom |
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25% |
Image bottom |
image height Lens center |
Lens center |
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Calculating Image Offset
Image height = 100 inches
Image offset = 125%
125% - 100% = 25% or 0.25
0.25 x 100 inches = 25 inches
25 inches from center of lens to screen
Actual distances may vary from calculations.
These calculations will approximate the location of your projector and screen. Always test calculations before permanent screen and projector installation.
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Lens center |
25% |
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25” |
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image height |
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Image top |
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100% |
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Ceiling Installation |
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100” |
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image height |
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Image bottom |
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Image top |
Table Top Installation |
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100% |
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100” |
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image height |
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Image bottom |
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25% |
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25” |
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image height |
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Lens center |
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