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Glossary
3D-Noise Filter:
Is an enhanced form of digital noise reduction. The ad-
vancement in technology enables noise to be filtered even more effec-
tively from the image, even in low light conditions.
50Hz:
Is the mains frequency used in the UK, Australia and most Euro-
pean countries.
60Hz:
Is the mains frequency used in the United States, Canada and
some Latin American countries.
AGC (Automatic Gain Control):
In low light conditions, the camera will
automatically boost the gain control so that people and objects can be
seen more clearly. The advantage of this technique is that your camera
will produce images in much lower light conditions. The downside is
that the amplification will increase the video noise visible.
Anti-flicker:
As fluorescent lighting operates at the same frequency
as your mains power, this will cause luminance flicker when viewed
through the camera. Enabling the anti-flicker options available can re-
duce or eliminate the flicker that is visible.
Anti-smearing:
A smear effect means that a bright vertical line orig-
inating from a bright light source appears in the image. This happens
especially with back lighting. Enabling this allows people and objects to
be seen correctly against a very bright background.
AP Mode:
This mode allows wireless communication with the provided
cameras, however, your DVR must be physically connected to your rout-
er to gain Internet access.
Auto DNS (Domain Name System):
A service that stores domain names
and translates them into Internet protocol addresses. For example,
www.google.com will have a DNS server address that is equivalent to
74.125.224.72. For this option, the DNS server is automatically provided
by your Internet service provider.
Auto-focus:
Will adjust the lens of your camera to focus on an object
being viewed.
Bit rate:
The amount of data that your DVR will use to record video.
The higher the bitrate, the more space each recording will consume on
the hard drive. Increasing this will also consume more bandwidth when
streaming. Unit of measurement is either Mbps (megabits per second)
or kbps (kilobits per second).
BLC (Back Light Compensation):
Improves exposure of an object that
is in front of a light source. It does this by splitting the whole image into
different regions, and then applying separate exposure levels to those
regions.
Brightness:
This changes how light the image appears to be. Its value is
different in darkness to that in daylight. For example, the lights from car
headlights appears to be brighter at night.
CDS:
This allows the image to be set by the camera’s light sensor. A CDS
sensor is basically a resistor that changes its resistive value (in ohms)
depending on how much light is shining onto the sensor.
Contrast:
This increases the difference between the blackest black and
the whitest white in the image. Without contrast there wouldn’t be an
image because there would be no differentiation between light and dark.
DDNS (Dynamic DNS):
Is a service that converts IP addresses into host
names (this is a lot easier than trying to remember an IP address). This
makes DDNS a good fit for home networks, which normally receives an
IP address from the ISP that will change occasionally.
