Sales and marketing people have known for years that there is an incomprehensible mental link between the quality of light and the human emotions that they create. Cold light conveys feelings of isolation, loneliness, and emptiness - feelings you'd hardly want from a product, but very useful if you want to exploit perceptions to enhance before-and-after images (eg. in fitness magazines, when hawking health supplements, etc). Exploring this link with colored lights is an easy approach, but un-necessary given the tools at your disposal with a high resolution photograph and Photoshop!
LINK:
http://www.psdtop.com/tutor/3022