Polaroid Polaview 220 manual Focus the projected image with the FOCUS control either

18Using the projector

Focusing and zooming		Focus the projected image with the FOCUS control either
the image		on the control panel or remote control. Adjust the image
		size by using the ZOOM control on the control panel or
		remote control.
Keystone correction		A keystone correction of 17 degrees is built into the
		projector to compensate for image distortion. You may
		want to adjust the rear feet of the projector to position
		the image on the screen.
Image size		The projector 20–30mm (1.5:1) motorized zoom/focus lens
		provides a high-quality display that ranges from 36 to 240
		inches (diagonal). The size of the projected image changes
		as you move the projector closer to the screen or adjust the
		zoom lens. The following table indicates the minimum and
		maximum distance from the projector to the screen for
		most standard size projection screens.
		Projected image	Distance from projection screen
		(diagonal)	Minimum	Maximum
	36 in.		42 in.	62.4 in.
	60 in.		70.8 in.	104.4 in.
	120 in.		141.6 in.	208.8 in.
	180 in.		211.2 in.	313.2 in.
	240 in.		282 in.	417.6 in.
		If you wish to compute your own measurements, use the
		following formula:
		MIN 20mm:	Diagonal/.85	= Distance from screen
		MAX 30mm:	Diagonal/.574 = Distance from screen