Looked different in Person of Interest vs. White Collar

It may seem a bit strange but I thought she looked/acted/sounded very different in Person of Interest than in White Collar (this being especially notable since she wasn't playing extremely different characters and wasn't wearing any special disguises or character makeup). She wore normal clothes in both and also had the same long brown hair. I don't know...her face seems slighter rounded in POI? And maybe it's some other stuff but I can't really put my finger on it. Weird. Does anyone else feel this way?