THORLABS DCC1 45 Series, Руководство пользователя

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70 DCx camera
© 2010 Thorlabs
6.5 Automatic Image Control
The DCx driver provides various options to automatically adjust the image capture parameters to the
lighting situation. These include:
Auto Exposure Shutter (AES)
Auto Gain Control (AGC)
Auto White Balance (AWB)
Auto Frame Rate (AFR)
The auto functions are used to adjust the average brightness and color rendering of the camera
image to their setpoint values, while trying to keep the frame rate at the highest possible value.
Auto Exposure Shutter (AES)
The control of the average brightness is preferably achieved by adjusting the exposure, i.e. you set
the highest possible exposure time before gain is controlled. Auto Exposure always uses the current
exposure range which results from the selected pixel clock frequency and the frame rate. You can
set separate control range limits for exposure and gain.
Auto Gain Control (AGC)
The auto gain feature controls the camera master gain in a range from 0-100%. You can set
separate control range limits for exposure and gain.
Auto Frame Rate (AFR)
With the exposure control function enabled, you can still change the frame rate manually or
automatically to maintain a dynamic exposure control range. A lower frame rate allows for longer
exposure times, but then the live image display may exhibit jitter. The objective of the automatic
frame rate control is to set the frame rate to an optimum value. This way, in all situations, the
automatic exposure control can use the required control range at the highest possible frame rate.
Auto White Balance (AWB)
Depending on the lighting source, light can have different color temperatures so that the images may
have a color cast. At low color temperatures (e.g. light from incandescent lamps), the white content
is offset towards a red hue. At high color temperatures (e.g. light from fluorescent lamps), the white
content is offset towards a blue hue.
The white balance control feature uses the RGB gain settings of the camera to correct the white
level. This is achieved by adjusting the gain controls within the 0-100% range until the red or blue
channel matches the average brightness of the green channel. In order to manually influence the
color rendering, you can adjust the setpoint values for the red and blue channels relative to the green
channel by using an offset value.
Automatically Disabling the Control Function
You can disable the control functionality automatically once the target value has been reached.
Alternatively, you can keep the control feature enabled so that it responds to deviations from the
target value.