Dell Projector 4100MP - Manual (Page 20)

CAUTION: To avoid damaging the projector, ensure that the zoom lens and elevator foot are fully retracted before moving the projector
or placing the projector in its carrying case.
1 Elevator button
2 Elevator foot
3 Tilt adjustment wheel
Adjusting the Projector Zoom and Focus
1. Rotate the zoom tab to zoom in and out.
2. Rotate the focus ring until the image is clear. The projector focuses at distances from 3.9 ft to 39.4ft (1.2 m to 12 m).
Adjusting Projection Image Size
1 Zoom tab
2 Focus ring