Smartbox Grid Pad Manual page 54

Different eye gaze cameras have their own optimal distance.
Ideally the camera should be placed so it is between 50cm and
70cm from your eyes.
Use the Grid 3 eye gaze monitor window to help you find the right
distance and angle. This is found in Settings – Access – Eye Gaze
– Calibration. Some cameras have a live view option, which will
give you a video feed from the camera.
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