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This problem keeps coming up again and again. I have tried to use the Dither checkbox in a Layer Effect in Photoshop CS6+ but that doesnt always work so well.
And applying a grain effect or noise effect just looks horrible sometimes.
It might be that I am not doing this correctly so would love feedback or leads to online tutorials that really solve this issue.
NOTE: I am preparing graphics strictly for web — so need to make gradients smooth in all displays including Apple Thunderbolt Displays, iPhone, iPad and even crappy monitors with low color gamuts.