UFC 4-021-02NF
27 September 2006
change 1, 23 October 2006
4-4
VIDEO MATRIX SWITCHERS
4-4.1
Video matrix switchers are components that provide switching capability
between cameras and viewing monitor displays. They typically offer functionality that
allows programmable settings such as loss of video alarms, camera naming, guard-tour
camera sequences, and salvo switching, which activates several cameras
simultaneously to pre-set views. Video matrix switchers can simultaneously switch
pan/tilt/zoom (PTZ) control signals with the video, so that control follows the active
camera.
4-5
KEYBOARDS
4-5.1
Keyboards allow an operator to control pan/tilt/zoom cameras. They are also
used to identify which camera to call up and display on the screen. Some CCTV system
keyboards come with "track balls" or joy sticks that facilitate camera control.
4-6
CAMERAS
4-6.1
Color versus Black and White. Color cameras offer more information such
as color of a vehicle or subject's clothing. Some ultra-low light color cameras are able to
automatically sense the ambient light conditions and switch from color to black and
white in low light conditions. Cameras must have auto-white balance to adjust for the
changing color temperature of daylight and artificial lighting needed for night-time
viewing. Black and white cameras are more sensitive under low-light or darkness
conditions and are best used when IR illuminators are required. These cameras are
further described in the Viewing in Low-Light Conditions Section of this chapter.
4-6.1.1 Color cameras require a higher illumination level than black and white
cameras to be effective. Typically, a high-quality color camera will work well down to 1.5
footcandle (fc) illumination, whereas a standard black and white camera might only
require 0.5 fc. These lighting level requirements vary with the camera model and
manufacturer, so be sure to specify the necessary illumination level that is required for
camera observation, and coordinate carefully with the lighting levels for the particular
area to be viewed.
4-6.2
Indoor Cameras. Indoor camera installations reduce the complexity of the
system, but care must be taken to correctly specify the lens, field-of-view and camera
hardware. Indoor cameras need:
4-6.2.1
Sturdy, secure mounting.
4-6.2.2
Auto-iris for lighting control.
4-6.2.3 Auto-white balance to ensure proper color correction to accommodate
changes in color temperature of lighting if it is dimmed or lighting is changed due to a
light outage.
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