What it does
Reflects the image across an axis, or folds it into repeating kaleidoscope wedges.
The toy came first, and it was a phenomenon. David Brewster, a Scottish physicist studying light polarization, patented the kaleidoscope in 1817 and watched it sell by the hundred thousand before the patent could protect him. The optics are two mirrors meeting at an angle: whatever sits in the wedge between them is reflected into a full circle of copies, and the narrower the angle, the more petals in the flower. Two centuries later the same geometry runs as a shader, with the mirror angle a slider instead of a brass fitting.
The digital fold works in polar coordinates. Every pixel asks how far it sits from the center and at what angle, the angle is folded into a single wedge, and the wedge is mirrored onto itself so its two edges meet seamlessly. That last reflection is what separates a kaleidoscope from a cheap radial repeat: without it, each segment ends in a hard seam; with it, the pattern flows across every boundary like the object was grown that way. Moving the center point changes what falls inside the source wedge, which is most of the craft, since an interesting sliver makes an interesting mandala.
Symmetry does not have to be radial. The same fold flattens into a single mirror, left half onto right or top onto bottom, the music-video symmetry shot that makes faces uncanny and architecture cathedral-like, or into a four-way fold that quarters the frame. And the whole pattern spins: a continuous rotation of the sampling angle sets the mandala turning while the footage underneath keeps playing, which is where the effect stops being a filter and starts being hypnosis.
Signature looks
Mandala bloom
A many-sided radial fold centered on a detail of the frame, petals of image opening and closing as the footage moves. The classic toy, running on video.
Split mirror
One vertical mirror down the middle of the frame. Faces go symmetrical and slightly wrong, buildings become Rorschach architecture, the simplest fold with the strongest mood.
Endless spin
A slow continuous rotation on the wedge while the source plays, so the whole pattern revolves like a turning glass. Made for loops.
Try it on your own footage
This effect runs live in the Modulate editor, with layers, effect chains, masks, and keyframes. Free, no signup, nothing to install.
Common questions
What is the kaleidoscope effect?
An effect that folds an image into mirrored, repeating segments around a center point, producing radial symmetry from any source. It reproduces digitally what the optical toy does with angled mirrors: one wedge of the scene is reflected around a full circle, so the output is a symmetric pattern that moves whenever the source does.
How does a real kaleidoscope work?
Two mirrors run the length of the tube, meeting at an angle. Light from the object chamber at the far end bounces between them, and each bounce adds another reflected copy of the wedge between the mirrors, filling the circle with symmetric repeats. The angle between the mirrors sets how many copies fit: narrower angle, more segments. David Brewster patented the design in 1817.
What is the difference between a mirror effect and a kaleidoscope effect?
A mirror effect makes one reflection: half the frame flipped onto the other half, one axis of symmetry. A kaleidoscope repeats that reflection around a center point, folding the image into many wedges of alternating orientation. They are the same operation at different counts, which is why editors often ship them as one effect with a segments control.
Why do kaleidoscope patterns look seamless?
Because each wedge is mirrored onto itself before it repeats. Adjacent segments always meet edge to edge as reflections, so the image flows across every boundary instead of jumping. Skipping that fold and simply rotating copies around the center leaves visible seams at each segment edge, which is the tell of a lazy implementation.
How do you make a kaleidoscope video?
Apply the effect to footage rather than a still: the symmetry is computed fresh every frame, so any movement in the source ripples through every wedge at once. In Modulate the Mirror / Kaleidoscope effect runs live on video in the browser, with the fold center draggable in the frame and a spin control for continuous rotation, and it exports as a clean loop.
Related effects
Spherize effect
Wraps the image onto a sphere — the disk bends over the ball, on a flat colour or transparent background.
Reeded glass effect
Looks through ribbed glass: rounded vertical flutes that bend and repeat the image like a textured shower door.
Wave effect
Bends the image with moving distortion: swirling turbulence, rolling directional waves, or rings spreading from a point.
Edge warp effect
Pulls the image toward the center and squeezes a stretched, magnified band around the edges, like looking through thick curved glass.