How to correct barrel distortion in photos
Most consumer-grade cameras introduce a certain amount of "barrel distortion" in the pictures they take. The distortion is most easily visible at 1x zoom, in the form of a bulge in the middle of the image, and less visible to non-existent at maximum zoom.
The real problem with this distortion is that most people don't know about it, and it's not readily recognizable in photos of people or other subjects that don't feature straight horizontal lines. This makes human faces look bulged in photos and hence, un-photogenic.
The good news is that you can correct this distortion through software. The most powerful software I found for distortion correction is ePaperPress PTLens. It ships with a database of camera distortion parameters and can automatically compensate for barrel, perspective, chromatic and other distortions.
Showing changes from previous revision.