TSA does not prohibit photographing, videotaping or filming at security checkpoints, as long as the screening process is not interfered with or sensitive information is not revealed.
Interference with screening includes but is not limited to holding a recording device up to the face of a TSA officer so that the officer is unable to see or move, refusing to assume the proper stance during screening, blocking the movement of others through the checkpoint or refusing to submit a recording device for screening.
Additionally, you may not film or take pictures of equipment monitors that are shielded from public view.