What is Automatic Gain Control?
In low-light conditions, some security cameras use Automatic Gain Control
(AGC) to artificially improve their “dynamic range” and produce usable
images. AGC is basically a from of amplification where the camera will
automatically boost the image received so that objects can be seen more
clearly. In normal light conditions the camera will display a normal
picture. However, when the light quality drops below a certain level the
camera will begin to boost the signal to compensate for the lack of
light.The advantage of this technique is that your camera will produce
images in much lower light conditions than standard.
What is Auto Tracking White Balance?
White Balance allows the camera to adjust the tone according to the color
temperature of the light source illuminating the subject. It allows the
operator to see objects as they appear during daylight. Simply put, AWB is
another image amplification feature designed to bring out the best
qualities of the images provided by your camera.
What is Auto Backlight Compensation?
Generally speaking, with ABC the camera can sense the whole area of the
frame and measure the average light level. The working point will be based
on general testing of the whole environment. If there is a very bright
background with a very dim front image, back light compensation is
activated so that the camera can apply light to the dark zone. With this
feature a normally dark and unspecific image can be easily transformed
into a clear and easily interpreted one.
Without Auto Backlight Compensation
With Auto Backlight Compensation
Difference Between Auto Iris Lens and Auto Electronic Shutter?
The
Auto Iris
is electronically controlled. This allows the camera to maintain the
lighting level by changing the spatial dynamic of the iris to obtain
optimal quality imaging. It is applicable in situations where lighting
conditions vary continuously. An auto iris allows the camera to adjust to
get the best picture in a given lighting condition. The Auto Iris can be
applied to both fixed and varifocal lenses.
The Auto Iris feature is highly flexible in producing consistent video
signals as it can adjust to drastically changing light levels. An
electronically controlled iris is perfect to maintain one consistent light
level making them ideal for outdoor use or any other applications.
AES - (Automatic Electronic Shutter)
is used in cameras where the iris remains fixed allowing the shutter speed
to change with response to the amount of perceived light to keep the
signal output at the best possible level. AES allows a fixed iris to adapt
automatically to different lighting conditions without the need of being
automated. When the shutter speed increases, the light passing through the
lens is decreased and the cameras sensitivity is reduced. When the shutter
speed is decreased, a larger amount of light enters the iris. For fast
moving objects the shutter speed can also be increased to provide a freeze
effect in order to provide higher resolution images.
Although both features are intended to account for changes in the lighting
environment, they both have their benefits and weaknesses. Whereas the
Auto Iris is used for optimal lighting maintenance, it is slower to react
than the Auto Electronic Shutter. Furthermore, the superior quality
imaging of the Auto Iris often comes at a higher price due to its much
more complicated structure. Both features are very important in achieving
quality imaging in varying light, and neither is better than the other.
They are simply better suited in different situations.
