What does panning involve in photography?

Panning in photography refers to the technique of capturing a moving subject while simultaneously moving the camera horizontally in the same direction as the subject's motion. This movement helps to create a sense of motion within the photograph and can lead to a striking visual effect, where the subject remains relatively sharp while the background appears blurred. This contrast emphasizes speed and movement, making panning a popular technique for photographing subjects such as runners, cars, or cyclists.

In this context, panning is specifically about scanning a scene horizontally, which aligns with the correct answer. The other options discuss different camera movements or adjustments that do not accurately define the panning technique. For example, moving the camera vertically pertains to vertical compositions rather than the horizontal motion essential for panning. Adjusting the aperture relates to depth of field and does not involve any motion technique. Tilting the camera may change a perspective but does not encompass the concept of capturing motion in a dynamic manner as panning does.