Vidikron 90 manual Ambient Light, Estimating Throw Distance

Installation

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).

In general, minimize or eliminate light sources directed at the screen. Contrast ratio in your	Ambient Light
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 and tips that can help improve your installation:	Other Considerations

•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 is the distance measured from the front of the projector to the screen. This is	Throw Distance
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.

Estimating Throw Distance

Throw Distance (TD) = Screen Width (w) x Lens Throw Ratio

Screen	width
		(w)

TD

Figure 3-2. Estimating Throw Distance

Vidikron Vision Model 90 Owner’s Operating Manual 3-5