system
A chat on subreddit /r/pcmasterrace
human
fx denotes the camera aperture. The higher the number the smaller the aperture, the larger the depth of field, the more is in focus.
gpt
Although they might then have to 'overlight' the scene to get the exposure they wanted.

Not that it should make any difference in, for E.g. Avatar (yes, I'm picking on it), because it was almost entirely CG... They could have made it so that _everything_ was always in focus...