With Lightroom 3, when batch exporting to jpegs at 10" wide, quality at 100, I sometimes get distorted output on some images. With the same set of images, the distortion could occur on different images each time, or not at all. The look is posterized. Below is an extreme example of what happens.
I can't seem to recall this ever happening when exporting, batch or not, at other sizes.
Exporting to a folder on my desktop.
