Honeywell EQUIP HD4DIP, Справочное руководство, Страница: 78 / 82

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Glossary
Iris Adjust Adjusts the iris either open or close in response to changing light conditions.
Line Lock Phase Adjust (LL-Phase Adjust, or Line Lock) When the camera is in Line
Lock mode it is synchronized using a fixed point on the A.C. supply’s cycle - usually the
point that the A.C. cycle passes through zero V. Usually selected by a switch on the side or
rear of the camera. This is commonly used to synchronize the vertical interval sync pulse of
your camera with other equipment in a switching system to reduce the effect of picture roll
on the monitor when two or more cameras cover a large site. You must phase the phase
for each camera. If multiple cameras are not synchronized correctly, the image on the
monitor rolls as the video switcher selects video from different cameras (frames arrive at the
video switcher at different times).
To utilize this feature, cameras must operate from an AC supply and be on the same Mains
supply phase. If they are not on the same phase, you can adjust them using the V-PHASE
potentiometer on the camera.
NTSC (National Television Standards Committee) A standard of specifications for
television transmission in the U.S., Canada, Japan, Central American, and half of South
America. The North American system uses interlaced scans and 525 horizontal lines per
frame at a rate of 30 frames per second.
PAL (Phase Alternate Line) A standard of specifications for television transmission for
color TV signals used in West Germany, England, Holland, Australia, and several other
countries. It uses an interlaced format with 25 frames per second and 625 lines per frame.
PoE (Power over Ethernet) A system designed to transmit electrical power, along with
data, to remote devices over standard twisted pair cable in an Ethernet network.
Shutter Speed The speed at which the charge is read out from the CCD chip. Adjusts the
light sensitivity of the camera. A faster (briefer) shutter speed can arrest the motion of a fast
moving object (reduce image blur), rendering it sharp. Fast shutter speeds allow less light
to all on the CCD and can darken the image. For fast shutter speeds, ensure there is
adequate lighting. Usually selected using dip switches on the side of the camera.
Subnet Mask A number used to identify a subnetwork so that an IP address can be shared
on a LAN.
True Day/Night The incorporation of a moving mechanical IR filter within the camera
ensures true 24 hour surveillance, providing high quality color images during the day and
similar quality black & white images at night when used with IR lighting.