VIVOTEK
72 - User's Manual
Before you start tuning the exposure related settings, please note that each Exposure mode contains
different congurable features. The options are shown below:
Exposure modes Configurable features
Auto > Backlight compensation
Shutter Priority > Exposure time
Iris Priority > Iris adjustment
Manual > Exposure time
> Iris adjustment
> Gain control
Exposure control:
■
Exposure level: You can manually set the Exposure level, which ranges from -2.0 to +2.0 (dark to
bright).
■ Automatic gain control: Selects the reasonable gain value to maintain a good picture. Note that the gain
level, lighting levels and picture performance are closely related.
■
Exposure mode: Select Auto, Shutter Priority, Iris Priority, or Manual mode according to your needs.
For example, if the camera aims to monitor fast moving objects such as trafc control, you might utilize
the Shutter Priority mode. Then, tune the slide bar to set the Exposure time and Gain Control to the
best image quality.
■ Auto Mode:
- Back Light Compensation (only available with the Auto mode): This option will automatically adjust the
display of images according to the brightness of an object which is at the center of a camera’s focus.
If you select the Auto mode, the Exposure time and Iris adjustment will be not congurable since the
sensor library will automatically adjust the value according to the ambient light.
■ Shutter Priority:
- Exposure time: The Exposure time setting allows tuning for more or less light into the lens. The
congurable value ranges from 1/10000 to the longest 1/1 second. An optimum shutter speed should
be maintained as long as the light level of the scene permits.
■ Iris Priority:
- Iris adjustment: The value is measured in the F-number as the ratio of the focal length to the lens
diameter. Iris size is inversely proportional to the F-number; therefore, the smaller the F-number, the
greater is the exposure ratio. Smaller F-number (larger exposure ratio, largest size of lens aperture
opening) is shown on the right of the slide bar.
■ Manual: (the Manual mode enables access to the congurable features above)
- Exposure time: see above for description.
- Iris Adjustment: see above for description.
