Digital Projection LIGHTNING 10sx, Руководство пользователя

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THROW DISTANCE - FIXED RATIO LENSES
It is important to position the projector at the right distance from the screen. This
'Throw Distance' is defined as the distance from the screen to the front of the
projector case. It is calculated by taking into account your screen width, the type of
lens used, and the aspect ratio you intend to display.
If you intend to display images with different aspect ratios, it is recommended that
you position the projector at a distance from the screen which will allow you to
project images at the maximum fractional aspect ratio (16:9 = 1.78, 5:4 = 1.25), i.e.
the image with the largest width. Failure to do so could result in smaller fractional
aspect ratio images exceeding the feight and/or width of your screen.
THROW DISTANCE - ZOOM LENSES
When using a zoom lens, exact positioning of the projector less important because
the image size can be adjusted. However, the projector must be located within the
Throw Distance range imposed by the minimum and maximum lens ratios.
If you intend to display images with different aspect ratios, it is recommended that
you define your own Throw Distance range. To define the minimum screen
distance, use the lowest lens throw ratio associated with the smallest fractional
aspect ratio used. To define the maximum screen distance, use the largest lens throw
ratio associated with the largest fractional aspect ratio used.
CALCULATING THE THROW DISTANCE
To calculate the distance between the screen and the front of the projector case use
the equation given below. The tables overleaf give the actual lens throw ratios (with
tolerances) and lens extensions. Perform the calculation for each end of the zoom
range to define the throw distance range. The tables also give the tolerance in throw
ratio if more accurate calculations are required.
Distance Required = (Screen Width x Actual Lens Throw Ratio) + Offset
BÑ5
System Installation
INSTALLATION
LBV00056; Revision A - 23/08/99