Just so other thread followers get it - the ACPU is ONLY for making patches for ICC profiling. Not for printing images as it has no colour management capabilities. As you may have discovered, it’s a recalcitrant utility - especially on Win where it appears to consistently resize the patch printout.
The colour engine should not be involved as there's no conversion.
As Bob mentioned - if colour management IS turned off in the driver, [and if the printer, inks and paper are identical AND heads clean (do a nozzle check)] then, when printing [in this case from the ACPU], one would expect the results to be the same.
Do make sure everything in the print driver is set the same between mac and Win.
If there is still a difference in appearance then perhaps that means that the achieved print from the Epson driver differs between Mac and Win, that’s not likely but it is possible, I imagine.
As you're printing characterisation patches with a view to making ICC profiles, maybe make ICC profiles for each and use a testimage to see if printed results match between Mac and Win, they should.
here's a free to use testimage: https://www.colourmanagement.net/downloads/CMnet_Pixl_AdobeRGB_testimage05.zip
IF I needed a profile for a specific paper/ printer on Mac I'd make it from Mac.
Why are you printing from both Mac and Win with the ACPU?
Maybe you need profiles for each - if so why not make 2 profiles?
That’s how I'd test it.
I hope this helps
neil barstow, colourmanagement net :: adobe forum volunteer
google me "neil barstow colourmanagement" for lots of free articles on colour management
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