Disable scroll-induced antialiasing in Preview and other PDF applications

Solution 1:

I suspect the blurring of text is caused by a low-memory proxy being used to ensure high FPS during scrolling, especially on Retina machines, probably when using integrated Intel graphics.

Therefore I would suggest doing the following steps in the below sequence, in order to maximize available RAM and VRAM:

• close all windows in all apps

• quit all apps

• disconnect any external monitors

• close extra desktops in Mission Control

• for machines with NVIDIA GPU, make sure your computer is plugged into the charger, or that Automatic Graphics Switching is turned off in Energy Saver

• if on a non-Retina machine, set "Best for display" in the Displays settings

• if on a Retina machine, set "Best (Retina)" in the Displays setting

• restart the machine or open Terminal and type "sudo purge", the hit enter, then quit Terminal

Note: the purge command takes a minute or two to finish. I've found it can really help to clear up RAM. Restarting does the same thing. Sometimes RAM does not automatically get freed up like it's supposed to without these steps, at least on 10.8.5 and earlier. It may not apply to 10.9 and newer, but it can't hurt to try.

If you would please, both before and after completing the above steps, open Activity Monitor and take note of how much memory, CPU, and disk data per second is being used. Post your before/after figures for Physical Memory and Memory Used in the comments (or Free memory if it shows that). Also let us know if the steps resolved your issue.