Glossary Of Cctv Camera Terms - Bosch Camera Reference Manual

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Glossary of CCTV camera terms

15-Bit technology
A method of more accurate and
sophisticated video processing.
Angle of View
The measure of the area within the
scene that is visible. The larger the
focal length, the smaller the angle
of view. The smaller the focal length,
the wider the angle of view.
Aperture
The size of the opening in the iris
controlling the amount of light
reaching the sensor. The larger the
F-Stop number the less light.
Automatic Gain Control
The electronics that regulates the gain
or amplification of the signal.
Auto Iris Lens
A lens that automatically opens or
closes the aperture in order to main-
tain proper light levels. With direct
drive or DC Iris lenses the camera
controls the size of the aperture.
Video iris lenses have the control
circuits built into the lens.
AutoBlack
Auto Black Compensation is a tech-
nique of boosting the video signal
level to produce a full amplitude video
signal even when the scene contrast is
less than the full range. The darkest
part of the signal is set to black and
the lightest part to white, thus
increasing the contrast.
Auto White Balance
A feature that allows a color camera
to automatically adjust its output color
to give a natural colour independent of
the lighting used.
Attenuation
A signal loss or decrease.
Back Focus
The distance between the image plane
and the rear most portion of the lens.
Back Light Compensation
BLC selectively amplifies parts of the
image to compensate for large contrast
differences when part of the image is
very brightly lit e.g. person in sunlit
doorway.
Cable Compensation
prevents image quality degradation
caused by signal losses from long cable
lengths.
"C" and "CS" Mount
Standard CCTV lens mount. "CS"
mounts normally used and have a
flange to sensor distance of 12.5mm.
Older "C" mount lenses, normally for
larger format sensors, can still be
found with a flange distance of 17.5
mm. Camera back focus adjustment
needs to be able to handle either type.
Charged Coupled Device (CCD)
The most common type of solid state
image sensor used in CCTV cameras.
The sensor converts light energy to
electrical signals.