Also, it captures a fraction of a second in time - but in real life we are always moving and changing. A smile, for example, involves many different movements, and sometimes a picture will capture a moment when your eyes are squinting, or the muscles in your cheeks are sticking out in an odd way. We don't notice these things in real life because remember the overall impression. But if everyone else thinks the picture looks like you, there must be some other explanation. That's because when other people see you, they see the same thing as you'd see in a photograph.
People tend to pick the image they are used to seeing.
Scientists tested this by asking people to compare photos and reversed photos of themselves and of their friends. Most of the time people picked the regular photos of their friends, but when the picture was of them, they chose the reversed photo. We tried this experiment out in our office. We reversed people's photos using an image-editing program on our computers. In most cases, though not all, the theory held true.