I do wonder how much of the difference is unintentional. I'm a photographer, and there are a lot of things (mostly flash, type/quality/amount of lighting, and exposure time) that can change skin tone -- among other colors -- dramatically. I once bought a pair of shoes off eBay, thinking they were an ugly purple color (Halloween). I mean, they looked PURPLE. When they came, they were burgundy (and cheap shoes, to boot!).