Teledyne Linea GigE 2K, User Manual

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Operational Reference Linea GigE Series Camera
Verify a Bright Acquisition
Aim the camera at a diffused light source or evenly lit white wall with no shadows falling on it.
Using CamExpert, click on the grab button and then the histogram button. Use the lens iris to
adjust for a bright gray approximately around a pixel value of 200 (for 8-bit pixels). The following
figure shows a typical histogram for a Linea GigE grabbing a bright gray image.
Important: In this example, the average pixel value for the frame is bright gray. Also note that sensors may
show a much higher maximum or a much lower minimum pixel value due to one or more "hot or dead pixels".
The sensor specification accounts for a small number of hot, stuck, or dead pixels (pixels that do not react to
light over the full dynamic range specified for that sensor).
Once the bright gray acquisition setup is done, note the camera position and lens iris position so as
to be able to repeat it during the calibration procedure.
Flat Field Correction Calibration Procedure
The following procedure uses the CamExpert Flat Field tool. Calibration is the process of taking two
reference images, one of a dark field – one of a bright field (not saturated), to generate correction
data for images captured by Linea GigE. Each sensor pixel data is modified by the correction factor
generated by the calibration process, so that each pixel has an identical response to the same
illumination.
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Start the Flat Field calibration tool via the CamExpert menu bar:
Pre-processing • Flat Field Correction • Calibration.