Pan Left

The camera turns to its left, so whatever sat at the left edge crosses the frame and leaves on the right. The audience is led backward across the space they have already seen.

In a film that reads left to right, leftward movement usually reads as return, retreat or going back over ground. That is a convention rather than a law, and it is strong enough to use on purpose.

The camera pivots left on a fixed point. The body does not travel, so no new depth appears during the move and the foreground never separates from the background.

Screen direction is set from the camera, not from the subject. A pan left turns the lens to the left, and the contents of the frame therefore travel right.

Name the frame it lands on. A direction with no destination gives you a turn that stops wherever the model decides it has done enough.

Use it to follow somebody moving left, and to go back to something already established, such as a door that was shown earlier in the scene.

Skip the direction entirely if it does not matter. Asking for a plain pan and letting the model choose is better than fighting it for a side that carries no meaning.

Dolly Left slides the whole camera to the left, so the foreground shears against the background and the view moves around objects. Pan Left turns in place and can never see behind anything.

The test is a near object. In a pan left it stays locked against whatever is behind it. In a dolly left it slides across it.

The model dollies instead of panning and the shot gains parallax it should not have. Say the camera turns on a fixed point with no travel, and ban dolly left by name.

The other failure is the wrong direction, which happens often because left is ambiguous between camera and subject. Say what the frame lands on at the end of the turn, and the direction fixes itself.