Why do so many people like to take photos of themselves with SLR as avatars?

1, blocking the face, seems to be less cliche than taking a selfie (in fact, it may be more because the face is not enough and the cameras are together).

2, narcissism, in fact, everyone is a little narcissistic, this is no exception, just a little shy.

3, attributes, indicating that you are interested in photography or small, but also a display of yourself, just like others use their own basketball photos as avatars.

4, literature and art, it seems that there are some literary models, why are there so many? That's why no avatar can ask why.