LightBurn 1.7 galvo calibration not working correctly

[joerg (Joerg Sonnenberger)]

Using 1.7.0.8 as the last version running on Linux. Can’t easily test 2.0 as the laser doesn’t want to appear under qemu.

I’m trying to calibrate a new ComMarker B6 galvo laser. After running the 9 point calibration, a test square is certainly properly squared, but does not have accurate dimensions. In fact, when setting to the scale parameters in the device settings, they don’t seem to affect the output size at all, just the speed e.g. of the framing pointer. Is it expected? How can I get both the lens correction and the correct output size to work?

[Aaron.F (Aaron)]

@joerg

when setting to the scale parameters in the device settings, they don’t seem to affect the output size at all, just the speed e.g. of the framing pointer.

That sounds odd. Do you happen to have a .COR file loaded here?

A .COR file sets everything, including the Scale values, and it’s not possible to use it and manually set only the scaling.

It should certainly not affect the Framing Speed. That one has its own settings further down in the Device Settings:

We now have fresh new docs on how to Calibrate the scale of the axes:

Galvo Lens Calibration - LightBurn Documentation

[joerg (Joerg Sonnenberger)]

I do have a .COR file loaded, but wasn’t completely happy with the result. Does that mean if I want to run the nine point calibration, I should remove the COR file first?

[Aaron.F (Aaron)]

@joerg

Does that mean if I want to run the nine point calibration, I should remove the COR file first?

Yes.
Ideally, it should automatically clear a .COR file when we run the calibration.

I’ve just run a test, and it appears that the .COR file stays loaded after the calibration.
You should see the bulge, skew, trapezoid values in the “Device Settings” greyed-out.
They only come to effect when you Clear the .COR file: