Pelco Manual C1937M-C (4/03)
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LENS SETUP AND FOCUS PROCEDURES
Video Drive Auto Iris Lens
Set the lens mode selector switch to AIV. Switch the ESC and AGC OFF. Refer to the lens instructions and
adjust the lens for the optimum picture (video output level of 1V peak-to-peak). To focus, fully open the iris
by covering the lens with a suitable neutral density (ND*) filter. If the viewed scene is 6.5 feet (2 m) away or
farther, set the lens focus to infinity (far). Use the back focus adjustment ring (refer to the Back Focus Ad-
justment section) and focus on the selected scene. Remove the ND filter and set the lens focus as required.
Set the AGC switch to ON, as required. Most scenes benefit from AGC.
Direct Drive (DC) Auto Iris Lens
Set the lens mode selector switch to AID (default setting). Switch the ESC and AGC OFF. Use an appro-
priate screwdriver to turn the lens level potentiometer (refer to Figure 1) fully clockwise. Next, slowly
adjust the potentiometer counterclockwise until the optimum picture is obtained (video output level of 1V
peak-to-peak). To focus, fully open the iris by covering the lens with a suitable neutral density (ND*) filter.
Select the scene to be viewed. If the viewed scene is 6.5 feet (2 m) away or farther, set the lens focus to
infinity (far). Use the back focus adjustment ring (refer to the Back Focus Adjustment section) and focus
on the selected scene. Remove the ND filter and set the lens focus as required. When finished, switch
the ESC and AGC ON.
Fixed Lens - No Iris
Set the ESC and AGC switches ON (default settings). To focus, set the lens focus to infinity and view an
image greater than 6.5 feet (2 m) away. Focus the image with the back focus adjustment ring (refer to the
Back Focus Adjustment
section). Set the lens focus as required.
Manual Iris Lens
Set the ESC and AGC switches ON (default settings). To focus, open the iris fully and set the lens focus
to infinity. View an image greater than 6.5 feet (2 m) away. Focus the image with the back focus adjust-
ment ring (refer to the
Back Focus Adjustment
section). Adjust the lens focus, set the iris (if equipped) for
the best picture quality. The largest aperture gives the best light sensitivity, the smallest aperture the
greatest depth of field.
Zoom Lens
Set the lens focus to infinity (far) and fully open the iris by covering the lens with a suitable neutral density
(ND*) filter. Zoom out to the widest field of vision and view a distant object. Adjust the back focus adjust-
ment ring until the object is in focus (refer to the Back Focus Adjustment section). Next, zoom fully in and
adjust the lens focus until the object is again focused. Repeat these steps until the full zoom range may
be viewed with the minimum loss of focus.
* NOTE: For best results, outdoors, use an ND3 filter.
BACK FOCUS ADJUSTMENT
The back focus adjustment is located at the front of the camera and is accessible from either side of the case
.
To adjust the back focus:
1. Loosen the two back focus lock-
ing screws (one on each side).
2. Turn the back focus ring until the
object is in focus.
3. When the back focus adjustment
is satisfactory, tighten the locking
screws. Do not over tighten the
locking screw or force the back
focus adjustment ring.
Figure 5. Back Focus Adjustment
BACK FOCUS
ADJUSTMENT
LOCKING SCREW
COUNTERCLOCKWISE
CLOCKWISE
BACK FOCUS
ADJUSTMENT
RING