It could be purple fringing which is an issue with many consumer digital cameras, whether this is an issue with the high-end DV cameras used on EPIII I am unsure of.
It's cause is debatable, but the general consensus is that purple fringing occurs when the lens is wide open in a high-contrast environment. the highlights become overexposed and specular reflections tend to 'max out.'
In theory, the smaller the aperature, the less purple fringing should occur. Maybe this is why EPII is lit so damned brightly for the most part. Think Jedi temple scenes and all of the daylight backgrounds. The more light, the smaller the aperature, less purple fringing.
Less light (EPIII), bigger aperature, more purple fringing.
This, of course, is just me talking out of my ass here, as I don't know if purple fringing is an issue with the Sony HDCF950 used to shoot EPIII.