Samsung SP-H800 - Manual (Page 16)

Preparation
Installation and Basic Adjustments
16
1. You can adjust the size of image within zoom range by manipulating the Zoom Knob.
2. Focus the picture on the screen using the Focus Ring.
1 2
NOTE
Focus may appear dim if the projector is installed at a shorter than recommended distance. (Page 19)
Zoom Knob Focus Ring
INSTALLATION AND BASIC ADJUSTMENTS
Zoom and Focus Adjustment
Using the Zoom Knob and the Focus Ring