Q: Font in Preview blurry

Same issue, as of El Capitan 10.11.6 (15G31), July 19, 2016. Running on multiple Macs, including Mac Pro with 3.7 GHz Quad-Core Intel Xeon E5.

For the record, it's not just a little blurry, but almost illegible.

Persian_1123 - I think the reason your technique is somewhat successful is because your method results in view sizes of 100%, 150%, 200% etc. and not in irrational zoom ratios like 133% or 166%. Anyone who spends a lot of time in photo editing software knows that the effects of sharpening on an image are best evaluated at 100% or 50% or even 75%, but odd zoom sizes result in your screen interpolating and rounding the pixels in ways which create viewing artifacts that distort the actual sharpness.

When you start with 100% and use the keyboard commands to zoom in and out, Preview usually (but not always) selects tidy zoom ratios like 50% and 150%. When you resize a window with 'zoom-to-fit' enabled, you are much more likely to get untidy zoom ratios like 133% or 87% which require more pixel manipulation to display.

When I say your technique is 'somewhat successful' I mean 'making the best of a bad solution' - and not, 'a fix for Apple's screw up' - which still exists for me in OS 10.11.6.

I've unchecked font smoothing, and sent feedback to Apple, but I am still unhappy with Preview PDF quality. Tried using Safari - which does display PDFs better than Preview - but Safari is not as user friendly when changing display sizes. For example, Safari does not indicate what zoom level is being displayed - and I can't figure out how to get Safari to zoom to exactly, say, 150%.