You might not have thought much about this, but your perception of your own face is different than what other people see. The most frequent view we have of ourselves is in a mirror, which is a flipped version of how we really look. However, since the image we see is inverted, we often feel more comfortable with how we look in a mirror, as opposed to photographs. We also have the option of looking at selfies, which are even worse, since they distort our features due to the wide-angle design of the camera lens.
The closest representation of how others see us is via photographs, but depending on the lens type used, even photos can present distortions which don’t accurately represent our faces. We may think the camera is capturing us exactly how others perceive us, but those lenses often make some features more prominent than others, and thus quite different from how we really look. Another big factor which comes into play with looking in a mirror or at a photograph is that both are two-dimensional images, so we can never truly appreciate our own faces as the dynamic, three-dimensional countenances which others see.
There is a concept called the True Mirror which enables us to regard our own faces exactly as others do. For a great TED lecture on face recognition which discusses the True Mirror, check out this link:
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