Silent Witness SWX80, Руководство пользователя

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Document 900.0255 Rev 1.00 June 9, 2004
8
Adjust the Line Lock (Vertical Phase) for 24 VAC
Operation
Phase adjustment may be necessary in multiple camera installations to prevent
picture roll when switching between cameras. To adjust the vertical phase while
switching between two cameras, push down the left or right switch on one camera
until there is no vertical roll (see
Figure 3 ).
Note If the phase cannot be adjusted to prevent picture roll, reverse
the power polarity.
Adjust the Backlight Compensation
The backlight compensation (BLC) adjusts the electronic shutter speed of the
camera based on the light levels in specific areas of the scene. This adjustment
provides better image quality for scenes that are unevenly lit.
The BLC factory default setting is OFF (see Figure 4 ).
Precautions
The light emitted from the near-infrared light emitting diodes provides illumination
over a wide area. This light is not considered a risk to the unshielded human eye.
However, as with any light source, it is recommended that normal precautions be
taken to avoid unnecessary exposure. For example, avoid staring into the beam or
viewing directly with optical instruments at close range.
Note IR LEDs could be warm after prolonged use.