Why do some letters look odd at 100% but not 200%?
I'm looking at a document both in InDesign and, after exporting to PDF, in Acrobat, and the strangest thing is happening to my font; some letters are looking different than they should when shown at 100% but look normal at 200%.
Look at the example below on some select words from the document: the m, n, i and l all look like they have a few pixels of a descender when viewed at 100%. When I zoom into 200%, the problem corrects itself. Any idea what's causing this? I'd like to get it fixed, because this PDF will likely be viewed on computer and not printed.
If it means anything, the font is ITC Stone Sans.
This is an artifact, obviously, of wretchedly failed attempts to render vector information accurately on screen.
The problem may be specific to Stone Sans. Have you tried experimenting with something else? Something in the hinting information (although I don't know why you'd want to hint the bottoms of sans strokes) would be the hot suspect.
If the problem is more general than that one typeface, I'd look to your GPU vendor for an update, and would try the PDF on a couple of other systems.
I don't have Stone installed on my nearby systems, but I checked a number of sans of about the same stroke weight as your sample and could not see any issue. I'll be very interested in what you find out after trying the above, though.