what i meant there was completely irrelevant, because my brain thought i was responding to a completely different post, so please ignore that. it’s been that kind of day.
so, back on track here. i asked about where you were pulling the values because of this thread here, where i first started to try to understand scan gap in context of GF settings.
and in particular, in relation to this table:
if the formula you posted above is correct, then GF is claiming a fixed, constant scan gap of ~0.0007", which is very small.
from this article:
Most lasers come with a 1.5" focal length, which means a dot size of .003".
the GF has a 50mm/2" lens. and in their faq they say the dot size is about 0.008”.
so all of this leaves me a little confused still. is it possible that fixed constant number you posted has the decimal one spot too far left?
if the “about .008 in” number is correct, matching the scan gap (which seems fixed on the GF, if #2 in your translation is correct) would mean the proper DPI to set your photos (matching the #s in the table i posted above) would be 150. converting .008" to mm is .2032, which somewhere between the .17 and .25 gap in the table, but closer to .17, so let’s go with that.
To determine what DPI file to use based on the scan gap: 25.4 / scan gap = DPI
25.4 / 0.2032 scan gap = 125 dpi
and i’m still not sure this is right. this is part of what still drives me nuts sometimes with the lack of access to more specific (and industry standard) settings to work with the GFUI.