User`s manual
VIVOTEK
User's Manual - 51
Exposure control:
■
Exposure level: You can manually set the Exposure level, which ranges from -2.0 to +2.0 (dark
to bright). You can click and drag the circular pointers on the Exposure time and Gain control
slide bars to specify a range of shutter time and Gain control values around which the camera
can automatically tune to an optimal imaging result. You may prefer a shorter shutter time to
better capture moving objects, while a faster shutter reduces light and needs to be compensated
by electrical brightness gains.
■ BLC: When selected, a BLC window will appear on screen meaning that the center of the scene
will be taken as a weighed area. This option enables light compensation for images that are too
dark or too bright to recognize; for example, for the dark side of objects that is posed against
bright sunlight.
Auto: If you set Exposure mode as Auto, the Exposure time and Gain control will not be
congurable since the sensor library will automatically adjust the value according to the ambient
light.
■ Iris mode:
Select Indoor or Outdoor iris mode to adapt to the installation. The preset iris
aperture setting will apply.
Manual: Select Manual to set a xed exposure time, gain, and iris settings. Then, tune the slide
bar to set the Exposure time and Gain Control to the best image quality. A shorter exposure
time allows less amount of light to enter the sensor; while a higher gain control value generates
certain amount of noises.
■ Iris adjustment: Use the pointer to manually enlarge or reduce the aperture size.
■ Flickerless
: This function helps avoid the flickering on images because of the fast shutter
movement and the inconsistency between power line frequency (50 or 60Hz) and exposure
time. When selected, the exposure time will be forced to stay longer than 1/120 second. For
cameras that come with xed iris lens, setting the exposure time to longer than 1/120 second
may introduce too much lights to the lens. Users can use this option to observe whether the
result of long exposure time is satisfactory.
■ Maximum Exposure Time: Use the pointer to manually place a limitation on the maximum
shutter speed.
■ Maximum Gain Control: Use the pointer to manually increase or decrease the strength exerted
as electronic gains.
■
Exposure mode: Select Auto or Manual mode according to your needs.