Vivotek CC8371-HV, Руководство пользователя

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VIVOTEK
User's Manual - 63
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 semi-circular pointers on the Exposure time and Gain
control slide bars to specify a range of shutter time and Gain control values within 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 the electrical brightness gains.
■ Exposure mode:
When the Manual mode is selected, you can click and drag the semi-circular pointers on the
Exposure time and Gain control slide bars to specify a range of shutter time and Gain control
values within which the camera can automaticallly tune to an optimal imaging result. You can
also configure the iris size to control the amount of light. For example, 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.
The inclusive window refers to the “weighed window“; the exclusive window refers to “ignored
window“. It adopts the weighed averages methodology to calculate the value. The inclusive
windows have a higher priority. You can overlap these windows, and, if you place an exclusive
window within a larger inclusive window, the exclusive part of the overlapped windows will
be deducted from the inclusive window. An exposure value will then be calculated out of the
remaining of the inclusive window.
Include
Exclude
Weighted region
Ignored region
Include
Exclude
- Flickerless :
Fixed iris models can encounter image rolling band issues when operating under incongrous
power line frequency with fluorescent lights. To solve the problem, the Flickerless mode can limit
the exposure time to 1/120 ~ 1/5 second. For the Auto iris models, when the exposure time is
limited to 1/120 ~1/5 second, iris size is automatically adjusted, and that the image brightness
is appropriately adjusted. Although the chance is rare, for Fixed iris models, when the exposure
time is limited to 1/120 ~ 1/5 second, they may encounter image over-exposure. If the Flickerless
option is selected, and users discover over-exposure from the live view, they can disable the
Flickerless option.
■ BLC (Back Light Compensation): This option will automatically add a “weighted region“ in the
middle of the window and give the necessary light compensation.