Infinite Loop

The last frame matches the first, so the shot plays forever with no visible join. Nobody watching can say where it started.

It suits anything meant to be left running: a background, a display, a header. The viewer stops waiting for it to end and starts treating it as a state rather than a clip.

The action has to return to its exact starting position, and everything else in the frame has to stay put while it does. The camera holds, the light holds, the background holds.

Cyclical movement is what makes this possible. A wheel, a wave, a pendulum, a flame, a rotating object: all of them pass through the same position again and are the reason most loops are built from them.

Light is the usual thing that breaks a loop. A cloud crossing the sun or a lamp warming up puts a different brightness at the two ends, and the seam flashes on every cycle.

Use it for ambient backgrounds, product displays and anything that will sit on a page while somebody reads.

Skip it when the shot has to say something changed. A loop is built to refuse progress, so it cannot carry a beat.

A boomerang plays forward and then backward, so the subject retraces its path. An infinite loop runs in one direction and arrives back at the start.

The test is the middle. If the action visibly reverses halfway through, it is a boomerang.

The seam shows, usually as a jump in the light or a shift in the background. Say the final frame matches the first exactly and the light stays constant throughout.

The second failure is an action that cannot return, such as somebody walking out of frame. Pick a cyclical movement and name it: the wheel turning, the flag lifting and falling.