4Pelco Manual C718M (10/96)
5.0 ADJUSTMENTS
Your optics package comes from the factory adjusted
for a broad range of lighting conditions. For this rea-
son, you may find it necessary to adjust your optics
package to tailor the picture to your specific viewing
environment. The following adjustments can be made
to the optics package:
•Back focus
•Shutter speed
•AGC
•White balance
•V-phase (vertical phase)
The factory adjustments for the above controls are set
as follows:
➤Back Focus
Adjusted with the camera looking at an object 55
feet (16.76 m) from the lens. The results are a clear,
in-focus picture through the entire zoom range.
➤Shutter Speed
Factory set to the slowest speed available: 1/60
second.
➤Auto Gain Control
AGC ON/OFF set to ON.
➤White Balance
White balance has two positions; one is ATW (Au-
tomatic Tracing White), which is a feature that
continuously adjusts the camera for optimum color
reproduction. AWB (Automatic White Balance) is
a feature that retains current settings in memory
even when the power is off.
➤V-Phase (Vertical Phase)
Synchronizes the picture when multiple optics
packages are used in a system.
The location for the controls of the above features, ex-
cept for back focusing, are shown in Figure 4. The back
focus adjustment location is shown in Figure 3. The
following sections define the above features and specify
how to adjust them to gain the best system performance
in your environment.
5.1 BACK FOCUS
Back focusing involves controlling the distance between
the focal point of the lens and the image head. If the
lens is focused on the imaging head properly, a clear
picture is maintained through the entire zoom range.
The optics package has been back focused at the fac-
tory.
In some cases, additional back focusing may be re-
quired. Should this be the case, adjust the back focus
by moving the lens positions to zoom wide and focus
far. Then position the camera on an object with clean
lines such as a window seal, shelf, etc., at a minimum
distance of 55 feet (16.76 m).
The back focus adjustment screw location is shown in
Figure 3. Use a small, standard, straight-slotted screw-
driver to adjust the screw, which is recessed in the cam-
era housing. The mechanical movement of the screw
as the screwdriver is turned is about three clicks (or
detents) in either direction.
As you move the back focus set screw back and forth,
the distance between the lens and image head moves in
and out. You will be able to see the clean line come in
and out of focus. Continue to adjust the screw back and
forth until the optimum focus is obtained.
Figure 3. Back Focus Adjustment