Yes, it seems it is tradition that graphics are pushed as 'better' on mac, as originally, graphics software was written for mac...but nowadays, I think PCs are able to adequately compete.
Color calibration is a big issue, but even though you go through the colorsync utility that comes with Mac, it doesn't mean that your monitor is correctly calibrated...for something like that you need hardware to analyze a test an image on your actual monitor....ex: Spyder Calibrator ....
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