That is atypical, most of us get with less than 0.1” accuracy easily (like see the contest below that @jules and I had back in the day when I engraved my initials on a mustard seed and she engraved a grain of rice. There was a calibration run you could do (it used a sheet of draftboard and printed edge to edge and then the camera imaged it and produced a proper de-warp map to get pinpoint accuracy. And you could increase that using SnapMarks (if that is still a thing) which let you get extremely high repeatable accuracy on jigs. Also worse than 0.5” is like a loose belt or something (just press gently on the drive belts and make sure they are relatively tight, not guitar string tight but firm, if the nut on the idler wheel is loose it will slide and the belt is then too loose to accurately position the head). Also make sure the lens for the camera isn’t coated with gunk.
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