Laser camera calibration problems and how to fix them

Look at the symptom. If straight edges look curved or the calibration score stays low, the lens calibration is the problem. If the picture looks straight but the burn lands a few millimetres away from the overlay, the alignment is the problem. LightBurn reworked its camera tools in version 2.1; in any program, the same two steps decide the result.

• Curved edges, low score → lens calibration
• Straight image, wrong position → alignment
• Fix only the step that is wrong

Print the calibration board at 100 % and mount it flat on a rigid plate; a wavy sheet ruins the result. Capture it in clearly different positions across the whole field, including the corners, and tilt it slightly between shots. Avoid glare from lamps and the laser's own LEDs, and never change the camera resolution after calibrating. In Vextrify you capture up to nine positions and see the reprojection error after calculating.

• Board flat on a rigid plate
• Different positions, corners included
• No glare, same resolution afterwards

Redo the alignment whenever the camera, the bed or the workpiece height changes. Engrave the reference marks at low power on a flat material, take a sharp still image and click the centre of each mark carefully. In Vextrify you click nine marks and the remaining error is shown in millimetres; if it is high, one click was usually off, so repeat that step instead of the whole calibration.

• Re-align after moving camera or bed
• Sharp still image, precise clicks
• Check the remaining error in mm

A camera sees the top of the workpiece. A thick cutting board sits closer to the lens than the bed, so the overlay shifts towards the edges of the image. Align on material of the height you engrave most, or re-align for unusually thick pieces, and frame the job before burning.

• Thick material shifts the overlay
• Align at your usual material height
• Always frame before the burn