7
Installation Instructions
DISCRETE COSINE TRANSFER ON/OFF
Digital transmission uses video compression (usually based upon the difference in subsequent
frames) and the required bandwidth is therefore dependent upon the difference in scene
content. Features such as AGC and sharpness enhancement etc., can generate signal noise
which will be interpreted as a change in scene content and increase the bandwidth required to
transmit the video information. The Discrete Cosine Transfer (DCT) feature may be used to limit
the system bandwidth requirements when the camera is connected to a digital network via an
encoder. When set to
on
, the cameras AGC circuit is limited to 12dB and chroma suppression
is increased. The default setting is
off
.
SHARPNESS ON/OFF
This feature can increase the apparent sharpness of the perceived image by enhancing the
edges of objects within the scene. The default setting is
off
.
GAMMA SELECTION
Two different gamma correction options are available
0.45
and
1.0
. Use this switch to select
0.45
to provide increased visibility within the darker areas of a scene, or
1.0
for a more linear
response. The default setting is
0.45
.
AUTOMATIC GAIN CONTROL (AGC) ON/OFF
The Automatic Gain Control feature can improve picture quality when the level of scene
illumination is low. Select
on
or
off
. For most applications, the AGC feature should be
on
and is
therefore the default setting.
ELECTRONIC IRIS (EI) ON/OFF
The Electronic Iris (EI) feature compensates for excessive light levels by automatically adjusting
the shutter speed of the camera. Select
on
or
off
. The default setting is
off
.
SYNCHRONISATION SELECTION (LL/INT)
This switch is used to select the synchronisation mode of the camera. When the camera is
connected to an AC supply, the Line-lock (
LL
) mode can be used. This locks the cameras
frame rate to the mains frequency so that each camera in the system is triggered at the same
point on the supplys AC-cycle. See also
Line Lock Phase Adjustment Potentiometer
.
The default setting is
INT
.
POWER LED ON/OFF
In normal operation, the LED on the front panel of the camera is illuminated when power is
connected to the camera. This can cause problems with reflections when the camera is
located inside a camera housing or dome enclosure. Switch L, figure 1, allows the LED to be
turned on or off. The default setting is
on
.
