Basler ace acA1920-155, Руководство пользователя, Страница: 281 / 326

AW00123404000 Features
Basler ace USB 3.0 271
For general information about auto functions, see Section 8.12 on page 261 .
For information about Auto Function ROIs and how to set them, see Section 8.12.3 on page 263 .
8.12.5 Exposure Auto
Exposure Auto is the "automatic" counterpart to manually setting the Exposure Time parameter.
The exposure auto function automatically adjusts the Exposure Time parameter value within set
limits until a target average gray value for the pixel data from the selected Auto Function ROI is
reached.
Either Auto Function ROI can be selected to work with the exposure auto function.
The exposure auto function can be operated in the "once" and continuous" modes of operation.
If the Auto Function ROI does not overlap the Image ROI (see the "Auto Function ROI" section) the
pixel data from the Auto Function ROI will not be used to control the exposure time. Instead, the
current manual setting of the Exposure Time parameter value will control the exposure time.
The exposure auto function and the gain auto function can be used at the same time. In this case,
however, you must also set the auto function profile feature.
When trigger width exposure mode is selected, the exposure auto function is not available.
For more information about setting the exposure time "manually", see Section 6.9 on page 162 .
For more information about the trigger width exposure mode, see Section 6.4.3.2 on page 119 .
For more information about the auto function profile feature, see Section 8.12.6 on page 274 .
The limits within which the camera will adjust the Exposure Time parameter are defined by the Auto
Exposure Time Upper Limit and the Auto Exposure Time Lower Limit parameters. The current
minimum and the maximum allowed settings for the Auto Exposure Time Upper Limit parameter
and the Auto Exposure Time Lower Limit parameters depend on the minimum allowed and
maximum possible exposure time for your camera model.
The Auto Target Brightness parameter defines the target average gray value that the exposure auto
function will attempt to achieve when it is automatically adjusting the Exposure Time value. The
target average gray value may range from 0 (black) to 255 (white) when the camera is set for an 8
bit pixel format or from 0 (black) to 4095 (white) when the camera is set for a 12 bit pixel format.
The exposure auto function will not work, if the camera’s exposure mode is set to
trigger width. For more information about the trigger width exposure mode, see
Section 6.4.3.2 on
page 119 .