This was common in the late 70s and in the 80s, with one head PER COLOR, techniques. Ie a red head, a yellow head, a green head, and a blue head.
If your galvos have good linearity, ie old General Scanning or Modern Cambridge, this is not a problem. But Linearity costs money, and from what I've seen, few if any of the "cheepie" modern scan sets have it or even test for it. So you would have to UGC them in software for a match with graphics.
There are velocity corrected test patterns such as the "Laser Media Clone" pattern out there.
Nough Said!
Steve
Qui habet Christos, habet Vitam!
I should have rented the space under my name for advertising.
When I still could have...