Hardware manual

Camera Impact Reference Guide
Datalogic Automation Inc. 2-26
When Test Image mode is enabled, and you click the snap button, the test image selected in the Test Images
drop down is displayed in the image window. Test images are stored in the camera.
Internal Correction
If Enable Correction box is checked, the camera’s internal correction for gain and offset is used. You select
the desired correction set from the drop-down. This field is disabled for some camera types.
Modes
• Half Resolution: If the Half Resolution check box is checked, the camera scans every other line so
it acquires the image twice as fast with half the vertical resolution (and twice the gain). This setting
can be used for high speed applications.
• Digital Shift: Digital shift provides digital gain for the image. The digital value from the camera is
multiplied by the multiplication factor selected from the drop down.This will brighten darker
images by boosting the brighter parts and eliminating the darker parts. If the image is already
bright, increasing the digital shift can saturate it. Increasing the digital shift can also increase signal
noise present in the image. This field is disabled for some camera types.
• Vertical Binning Mode: If vertical binning is enabled, every other line of the scanned image is dis-
carded, then adjacent lines are added together. This produces an image that is half the original size,
but the averaging can brighten a dark image somewhat. Some of the signal noise present in the
image can be reduced. (This is similar to Half Resolution Mode, except the image size is reduced.)
This field is disabled for some camera types.
Set to Defaults Button
Clicking this button restores all camera settings to their factory defaults. Default settings are determined by
the camera type.
Save Image
Click this button to save the displayed image to a file.The image is saved in Portable Networks Graphics
(PNG) format.
Calibration Panel
NOTE: Access to functions on this tab may be limited based on the user’s access level and while the device
is online.
A camera will require calibration the very first time you use it, when the camera-to-subject distance is
changed, when a new camera is connected, or if the lens is changed. Calibration insures that the measure-
ments indicated in VPM tools accurately relate to the inspected object’s measurements. You may calibrate a
camera using a calibrated target or enter the camera’s units-per-pixel factor manually.
If you want to use partial scanning on an image, you must calibrate the entire image first and then set the
partial scan parameters.
Camera Calibration Technical Details
The dot centers in the image are matched to their known locations on the dot target. Any discrepancies due
to lens distortion or perspective distortion are compensated for by computing a best fit 2nd-order polynomial
mapping between the image dot centers and the known dot pattern of the target. Four mappings are com-
puted, one for each quadrant of the image. The mappings are of the form: