Screen size, Ambient light, Other considerations – Vidikron 90 User Manual
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Vidikron Vision Model 90 Owner’s Operating Manual
Screen Size: Choose a screen size that is appropriate for your lens and application. The size
of the room and viewing distance are the defining factors; a rule of thumb is that the primary
viewing distance be 1.5 times the screen width.
To fill a screen with an image, the aspect ratio of the screen should be equal to the aspect
ratio of the image (expressed as the ratio of its width to its height). Standard video from a
VCR has a 4:3 or 1.33:1 aspect ratio. For example, to display a VCR output with a 4:3 aspect
ratio onto a 10-foot (3.05-meter) high screen, the width of the screen must be at least 13.3
feet (4 meters).
Ambient Light
In general, minimize or eliminate light sources directed at the screen. Contrast ratio in your
images will be noticeably reduced if light directly strikes the screen, such as when a shaft of
light from a window or floodlight falls on the image. Images may then appear washed out
and less vibrant.
Other Considerations
Other considerations and tips that can help improve your installation:
• Keep the ambient temperature constant and below 35°C (95°F). Keep the projector away
from heating and/or air conditioning vents. Changes in temperature may cause drifts in
the projector circuitry, which may affect performance.
• Keep the projector away from devices that radiate electromagnetic energy such as motors
and transformers. Common sources of these include slide projectors, speakers, power
amplifiers and elevators.
Throw Distance
Throw distance is the distance measured from the front of the projector to the screen. This is
an important calculation in any projector installation as it determines whether or not you
have enough room to install your projector with a desired screen size and if your image will
be the right size for your screen.
You can quickly estimate the throw distance by taking the width of the screen and
multiplying it by the lens throw ratio; see Figure 3-2. The result of this calculation tells you
roughly how far back the projector should be positioned from the screen in order to project a
focused image large enough to fill the screen.
Figure 3-2. Estimating Throw Distance
Estimating Throw Distance
Throw Distance (TD) = Screen Width (w) x Lens Throw Ratio
Scr
een w
idth (w)
TD