I was using my Samsung LED 24" monitor via HDMI on my Windows laptop at factory settings (No monitor or windows calibration) and it was perfect. I have connected my macbook pro using thunderbolt to HDMI adapter and the colours/text look dreadful. Contrast is extremely high, unable to distinguish grey from white! The monitor is set at the correct resolution (1080p) in Display preferences. I have done a Mac calibration (advanced) from display preferences and its a lot better but still bad compared to windows laptop. Why does the wizard ask to put the contrast up to 100% to start? My monitor is set at 55% by default which was perfectly fine on windows. why are the colours so bad, particularly greys? i.e. the apple UI. I have lost the ability on the monitor to configure HDMI black setting (its greyed out) now that the macbook is plugged in. I have found historically external monitors look crap on Macs, whereas windows 99% of the time just WORK. Any tips? My monitor is S24A350H.