Manual

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Firmware User’s Manual V7.00.44
71
In extreme low light conditions, the shutter speed is slown down to get more light into one image,
but not slower than the user defined threshold.
If the exposure time extends beyond the interval between frames (too slow shutter), (i.e. 1/30
second), then the frame rate will be automatically reduced. Longer time in this value gives
clearer images at night for slow moving objects, but more motion blur for fast moving
objects.
White balance refers to the capability of the camera to understand what “true white color is”.
When the camera knows the true white color, then the rest of the colors will be accurate, too.
While human eye can easily adapt to different lighting sources (even mixed sources, such as sun
light through the window and indoor lights turned on at the same time), the camera has to
understand what is the dominant light source in given scene and what is the “white color” of such
light source.
By default the camera is in auto white balance mode and attempts to recognize the light source
and its color spectrum automatically and adjusts the image accordingly. This function works
continuously in the background. It is re-evaluated for each frame, to make sure if there is any
change in dominant light source (e.g. the user closes the curtains to block the sun light and turns
on the indoor lights).
In most cases the auto white balance works perfectly and the user does not have to adjust
anything! In some rare installation cases, especially when there are no white color objects in the
field of view, and the light sources are mixed, the camera may have difficulty to identify the true
white color to fine tune the rest of the colors.
In such cases, the installer can “help” the camera to understand the true colors by placing a white
object (for example a piece of white paper) in front of the camera to cover the whole field of view
and wait a few seconds – the auto white balance system will adjust the colors until the white
paper will really look white on the display. At that moment, the user can freeze these white
balance settings by pressing the Hold button. After pressing that button, the White Balance will
switch from Auto mode to Manual mode, together with the color values captured at the moment of
Hold. The user can now remove the white object from the field of view, and the colors will stay
correct for given scene.