Difference in horizontal vs vertical burning

So I’m using an ORTUR laser engraver and I’ve noticed that whenever I engrave vertically (90 degree, blue tile) I get significantly better results, but the color difference at different power levels is lacking. Engraving horizontally (0 degree, red tile) I get a good gradient but looks significantly worse. Is it possible that I need to change the scan gap when engraving horizontally vs vertically?

It occurred to me after I posted that the beam being elliptical would act differently going side to side and up and down. I’ve been experimenting with scan angle and it’s working better, but still a little inconsistent.