Nortel Networks 83c User Manual

Try to place the projector directly in front of the center of the screen, 
facing it toward the screen squarely. If the projector isn’t positioned 
this way, the image will be “keystone” shaped, instead of square or 
rectangular.

If you place the projector below the level of the screen, you’ll have to 
tilt it up by extending the front adjustable foot, as described on 
page 39. This also causes the image to lose its rectangular shape. You 
can adjust the shape using the buttons on the projector (see page 40), 
or using the projector’s menu system (see page 49). 

The Auto Keystone feature corrects the distortion automatically. See 
page 57 for more information about Auto Keystone correction. If 
necessary, you can adjust the image shape manually as described on 
page 40. 

You can also project from behind the screen or from the ceiling, with 
the projector mounted upside-down: 

To project from overhead, you’ll need the optional ceiling mount 
hardware. (See page 13 for ordering information.) You’ll also need to 
select 

Front/Ceiling

 or 

Rear/Ceiling

 for the Projection option in the 

Extended menu. To project from the rear, select 

Rear

more information.

Front/ceiling projection

Rear projection (using a 
translucent screen)

Rear/ceiling projection (using 
a translucent screen)