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PEAK WHITE INVERSION ADJUSTMENT POTENTIOMETER
The Peak White Adjustment potentiometer allows you to set the threshold point at which the
Peak White Inversion feature becomes active when it is switched on. See also
.
LINE LOCK PHASE ADJUSTMENT POTENTIOMETER
When the camera is in line-lock mode it is possible to adjust the point on the AC cycle at which
the camera triggers. This facility is provided so that cameras that are connected to different
mains phases may still be synchronised.
The line lock phase adjustment potentiometer allows the line lock phase trigger point to be
adjusted by ±120
. Rotating the potentiometer clockwise advances the trigger point and turning
O
it anticlockwise retards the trigger point. The factory default setting is the zero crossing point.
If all cameras in a system are on the same mains phase then no line lock phase adjustment
should be made—see also
.
DD LENS LEVEL ADJUSTMENT POTENTIOMETER
The DD lens level is controlled by this potentiometer. The video output signal is converted into a
DC voltage by circuitry within the camera. The potentiometer sets a reference voltage against
which this derived DC voltage is compared. If the DC voltage is less than the reference level,
the lens iris opening is increased. If the DC voltage is greater than the reference level, the lens
iris opening is decreased. This control loop attempts to continually match the DC voltage derived
from the video signal, to the reference voltage set by the potentiometer. This feature allows the
installer to set the required video output amplitude (e.g. 1V pk-pk) that the lens should strive to
maintain.
DD PEAK AVERAGE ADJUSTMENT POTENTIOMETER
This potentiometer determines how a DD lens reacts to the scene illumination. If the potentiometer
is set towards
, the brighter areas of the scene will be correctly exposed potentially
resulting in other areas of the scene being too dark. If the main area of interest in the scene is
particularly bright, then the setting should be towards
. If the brighter areas of the scene
are not of interest, the setting should be more towards
. This may result in the
highlights within the scene being over-exposed but should improve the contrast in the darker
areas of the scene.
This feature is integral to video drive lenses. The level and peak circuitry included in the camera
means that it is possible to replicate the performance of video drive lenses when using DD
(Direct or D.C. drive) lenses which are typically less expensive.
AUTO-IRIS LENS TYPE SELECTOR SWITCH (VIDEO DRIVE OR DIRECT DC DRIVE)
This switch allows you to select the type of automatic iris lens that is connected to the
connector on the side of the camera. Default setting is
(Direct or D.C. drive).
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