Calibrating the Background Light Level

The image seen by the camera may include some of the framework outside the illuminated table, and the brightness of the table may vary from one part to another. To eliminate this unchanging background data from the product image the system stores a reference background frame which is subtracted from the measurement frames.

Every time the program starts up it will display a dialog box asking for (background) calibration. Switch on the light box and remove any product or other obstructions from the table. Once the image in the viewfinder has stabilised, press a trigger. This can be the control panel black button,, the space bar, enter or return key on the keyboard or clicking the mouse on the cancel button. The background image will be displayed in the capture window.

The background can be recalibrated at any time by clearing the table and clicking on the calibrate button or on the control panel pressing the black button while holding down the up button.

After a background calibration operation the capture window shows the background image which will be subtracted from each captured image.