1080p - MacOS X - Screen / Font rendering very bad
Solution 1:
This Mac OS X Hints tip describes how to fix the problem:
In Snow Leopard, you can only choose between Automatic and Standard CRT. Since few people use CRTs these days, most users now have only one option: Automatic. The problem with the Automatic option is that OS X incorrectly detects many third party LCD monitors as CRTs, and consequently, disables LCD font smoothing.
You can force OS X to use LCD font smoothing on all displays with this Terminal command:
defaults -currentHost write -globalDomain AppleFontSmoothing -int 2
The number
2
here corresponds to Medium - Best for Flat Panel. You may also use 1 for light smoothing, and 3 for strong smoothing, as per the original OS X font smoothing options.
You'll have to relaunch applications to see the effect in them.
Solution 2:
I have the same monitor -- I had to turn on the Samsung "Magic Color" setting to fix that problem. No amount of calibration would solve it. Font smoothing 2 is also recommended as per the previous hint, but it was turning on Samsung's weird "magic color" crap that got rid of all the weird white antialiasing that was happening around the letters.
Solution 3:
I've had similar problem and I get things better (but not perfect IMHO) changing the configuration on the monitor OSD :
Menu Conf & reinit Mode PC/AV : PC
Note that I use a 2008 macbook pro connected by a DVI-HDMI cable to the monitor