Philips PCA646VC Installation Manual page 16

The Flickerless option must only be used under flickering 50 Hz light
conditions (like fluorescent or neon lamps) to prevent flickering or
strangely coloured video images. If this option is used under normal
lighting conditions the video image will tend to be overexposed.
6.2.3 Image Controls
The third tab is marked 'Image Controls'. It is divided into the
subsections Image Controls and Defaults.
Image Controls
Here you will find the slider controls for brightness, contrast, and
gamma correction.
Note that both Freeze and Manual Exposure mode settings in the
previous tab disable the controls for contrast and backlight
compensation.Try a few settings to find one you like.
With the colour enable checkbox, you can switch from colour images to
black&white and back.
Turn on the backlight compensation to improve the image quality when
you have a scene where the background has a high illumination level (for
instance when you sit in front of a window).
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