finer control of Preview anti-aliasing (font smoothing)? I have just updated to Yosemite and something must have changed in the way Preview renders fonts. 

I find that Preview display of text in PDF files is rather sloppy, I am pretty sure it used to be much sharper in Mavericks. At the very least now Preview is significantly less sharp than Acrobat Reader, you can check out a screen-shot to convince yourself of what I am talking about.

In the rest of the UI I am quite happy with how fonts are displayed. So I was wondering if there are ways to control the anti-aliasing of Preview. In the preferences of Preview I can find only a global switch for anti-aliasing, but I would like to play around with the strength of the anti-aliasing so to find the optimal setting. 

I am looking into defaults of com.apple.Preview but in my current values there seem to be no setting about Font Smoothing or anything evocative of anti-aliasing. Any suggestion about possible values to edit here?

Thanks for your suggestions,
Roberto
I have found a solution to this problem: replacing Yosemite's PDFKit with Mavericks' PDFKit. As simple as that. I replaced the contents of /System/Library/Frameworks/Quartz.framework/Versions/A/Frameworks/PDFKit.framework/Versions/A and everything is working fine now.

For those who don't have a copy of Mavericks from where you can take the PDFKit files, I have uploaded a copy to: http://www.filedropper.com/pdfkit (hope there are no copyright issues with this - I will remove the link if asked to do so).

By the way, changing the Current symlink to point to the Mavericks version and keeping the original A/ directory DIDN'T fix the issue. I had to remove the Yosemite version completely and put the Mavericks version contents inside A/ (it seems Preview and Skim both are hard coded to Versions/A and do not follow the Current symlink).