Photogenic
A subject (generally a person) is photogenic if appearing aesthetically or physically attractive or appealing in photographs. Photogenic drawing, coined by Henry Fox Talbot, also describes the earliest method for recording images.
Physical attractiveness
The state of being photogenic may or may not necessarily be related to one's physical attractiveness in real life. Models are usually described as photogenic. The bone structure of their faces may represent something that is not generally pretty or may be even unattractive or frail looking, but when photographed, their features can turn into something that is physically attractive.
Charisma
Another explanation for the fact that attractive people are not always photogenic is that part of their attractiveness may be due to the charisma they bear in real life due to the way they move, express, carry themselves. While this will positively influence the subjective appearance of that person in real life, a still photograph usually fails to reproduce these attributes, possibly rendering a picture of the person less attractive than the real-life perception and contributing to classify that person as less photogenic.
Lighting
The lighting when the shot is taken can also have a large effect on a person's perceived attractiveness. Also, a person's face may look different depending on the angle and intensity of the light being reflected off the face. But, lighter skin tones and features may appear washed out when taken from a flash camera. This effect is magnified when a flash camera is used and may cause undesirable features, such as ridges or bumps, to appear more pronounced than they otherwise would.