User`s manual

4M30 Camera User’s Manual 25
DALSA 03-32-10030-03
The read user offset commands allow the user to read back this information from the
camera.
Reading Channel 4 Offset from the Camera
To read Channel 4 offset setting from the camera, use these commands:
Read MSB Read LSB
Binary 0111 0011 0111 0010
Hex 73h 72h
3.11 Automatic Offset Control (AOC)
The AOC defines the digitized value of black for the camera. An ideal camera (no dark
current, no shot noise, etc.) in total darkness produces an image with all pixels equal to
the AOC set point value. This command allows you to control the AOC set point of the
ADC video board. The four ADC video boards in the 4M30 can each be controlled
independently. Normally all channels are controlled with the same set point value. The
default value is 50 DNs, or counts.
Example: Set the Channel 2 AOC Set Point to 32 DNs
Value = 32
= 20h
Command Value
Binary 0001 1000 0010 0000
Hex 18h 20
3.12 No Clean Mode
There is no way to prevent the CCD imager from integrating (accumulating charge due to
light falling on the imager). Under some conditions this will cause the image to show
smearing in the vertical direction, and increase Dark Current. In order to reduce this
effect, the 4M30 camera runs horizontal and vertical clocks during idle time to flush the
charge. Under some conditions, this feature may be undesirable. For example, when
wanting to synchronize camera integration to an external event in the External
Integration Mode. Under these conditions, the user can enable the No Clean Mode by
setting bit [2] in the Control Register = 1. No Clean Mode can only be enabled when in
Programmed Integration Mode (bit [7] of the Control Register =1)