Circular mask that expands or contracts across frame — opens or closes a shot. Silent film staple, now mostly retro or stylistic.
You know this from old silent films: a black circle or oval moves across the screen, revealing—or hiding—what lies beneath. This is the iris wipe, and it works on a simple principle: a geometric shape moves across the frame, opening a new shot as it enters or closing the old one. In editing, this used to require a physical iris that was held in front of the lens; today, it's a digital effect you'll find in any editing software.
What's interesting is that the iris wipe was a narrative necessity in the silent film era. It clearly signaled to the viewer—often without dialogue—that one scene was ending and a new one was beginning. Because there was no soundtrack, visual editing markers had to be all the clearer. With the introduction of sound and later montage theory, the iris wipe quickly became an anachronism. Today, we use it intentionally when we aim for a retro aesthetic or ironically allude to older film language—in comedies, in homages, in art films.
On set, you don't need to pay attention to anything; this is purely editing work. In your NLE (Nonlinear Editing) software, you place the iris wipe between two clips and define: direction (from outside in or vice versa), shape (circle, oval, even irregular shapes are possible), speed, and starting position. Many editing suites offer pre-made presets, but be careful—used too frequently, it quickly looks amateurish. One iris wipe per scene change can work; more becomes a gimmick. Related to this is the iris diaphragm (an opening and closing circular aperture without movement), which is even older and feels even more like something out of a Chaplin film.
Modern editing applications also allow you to change the shape—stars, diamonds, asymmetric shapes—but this quickly veers into kitsch. If you want to use an iris wipe, stick to the classics: circle or oval, clear direction of movement, appropriate duration (around 12-24 frames). Make sure the moving shape doesn't obscure important faces or details for too long. And use it sparingly—it's a stylistic statement, not your standard transition solution.