chromasens allPIXA, Руководство пользователя

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CD40047_R04_allPIXA_User-Manual.docx 145
Example:
All desired values for the white reference target value are set to 800,
stop gain control factor is set to 0.5.
If sum of all current white references drops below 0.5 * 800 = 400,
then automatic gain control is disabled.
Set gain control stop by variance
Name
Name
Set gain control stop by variance
Function
Sets the pause condition for the white control.
Channels All
Unit Integer
Dependency
Takes only effect if the Stop gain control by variance value check box is
selected in the White control mode area.
Notes
White control pauses if medium variance of the values of the pixels in the white
reference area is higher than the specified value.
Camera: Value:
Lower limit All 0
Upper limit All 65535
During the scan, the camera is set to automatically control the image brightness by use of the
implemented function “Automatic white control”. The control mechanism of the camera uses the
reference area on the object to adapt the camera gain values as defined within the camera
parameters.
In rare situations, the Gain control stop factor parameter cannot be used successfully,
because medium brightness is similar to that of the expected object if no object is on the
transport. But in these cases often brightness variance of the pixels is much higher if no object
is present.
Select active channels for white control
Name
Name Red / Green / Blue
Function Determines which channels are active during automatic white balancing
Channels All
Unit
Dependency
Applies only to all automatic gain control functions such as white balancing
Notes
If you wo
rk with “white” illumination, leave all channels set to “Enabled” (Standard
use of the allPIXA wave).
This function is useful if you work with different lighting conditions.
If you are for example working with three different light setups for the different color
channels you could turn on the lights for one channel, disable the other “Active
channels” and perform white and tap balancing.
After this you run through the same procedure for the other channels. If you disable
the channel, the old values for the white or tap balancing are not overwritten.
Camera: Value CST:
Lower limit All 0
Upper limit
All 1,00