I've been vacillating a bit on ClearType recently. I love ClearType in theory. A threefold improvement in horizontal resolution on LCDs is an incredible step forward for computer displays. Internet Explorer 7 forces the issue a bit by always defaulting to ClearType for web content, even if you haven't enabled ClearType in Windows XP.
But in practice, I keep running into problems with ClearType enabled that drive me absolutely bonkers. Check out this shot of Hex Workshop, using the Consolas font, with ClearType enabled:
What's up with the hideous halation effects around the selected characters? It's unbearable! The obvious RGB noise around the characters is not helping readability at all.
Fortunately, the ClearType Tuner PowerToy lets us tweak this for the better. Switch to the advanced tab so you can use the ClearType Contrast Setting slider. The slider has a range of 1.0 to 2.2, and the changes take effect in real time.
Here's a shot of the same window with 2.2 contrast, the lightest possible.
The effect is exacerbated by reducing the contrast, so clearly we have a contrast problem. Let's try turning it all the way up.
Here's a shot of the same window with 1.0 contrast, the darkest possible.
Maximum contrast looks good, but it has an unwanted side effect as well-- now bold text looks terrible! Compare for yourself. Minimum contrast at the top, standard in the middle, and maximum at the bottom.
Bold text looks best with contrast set to minimum. I just can't win.
I'm currently compromising by sliding the contrast slider over a few notches toward the darker side-- a setting of 1.4 versus the default of 1.6. But no matter how I tweak the slider, there are always places where the text is less legible with ClearType on. Sometimes pathologically so.
I guess it's back to standard greyscale font smoothing for me. It's too bad, because I love Consolas, and I think ClearType is genius-- if they could get it to look good in all situations, and not just for black text on a white background.