Torn paper edge or paper fold — which one should you use?

A torn edge and a fold change different things

A torn edge is a silhouette operation. What you see is the image cut to a ragged outline, so the change happens at the boundary: the rectangle is gone, and what is left is a scrap with a raw paper core running along its rim. Everything that sells the effect — the uneven line, the exposed fibre, the shadow the scrap drops — hangs off that one cut.

A fold is a surface operation. The rectangle is still there; it is bent, and the bend reads because of shading and perspective. The outline moves a little in projection as the sheet turns, but the thing doing the work is the crease and the way light falls across it.

That difference decides which one you want, and it is worth stating plainly because the two are often sold side by side as if they were interchangeable. If the message is "this was ripped out of something physical", you want the torn edge. If the message is "a flat page is opening up", you want the fold. One is not a stronger version of the other.

It also decides what the tool has to be able to do. A silhouette can be drawn in two dimensions — no lighting model, no normals, just an outline and a fill. A fold needs a surface whose normal changes across it, which is a different piece of machinery entirely.

What actually makes an edge read as torn

The torn outline here is not a picture of a tear that gets scaled to fit your image. It is generated from the piece's own outline every time you load a photo.

The tool walks the rounded rectangle of the piece at a fixed step along its perimeter — about 4.6 px apart at the default Detail of 0.50, tightening toward 1.6 px as Detail rises — and pushes each sample along its outward normal.

The size of that push comes from value noise sampled by pixel position rather than by distance along the outline. That distinction is the whole trick. Keyed to pixels, the wavelengths stay put no matter how large the piece is; keyed to the outline, a long perimeter would stretch the same noise into a couple of slow lobes and you would get a bowed rectangle instead of a tear. Three octaves are summed: roughly 500 px, 180 px and 70 px, with amplitudes of 0.50, 0.18 and 0.06.

On top of that slow wander sits a per-sample jitter of a few pixels — about 1.2 + Detail × 4.5 px. It is added to the outer edge only, which means neighbouring samples are allowed to disagree. That disagreement is what reads as torn rather than as a smooth wobble; remove it and the edge turns into a gently wavy border.

The three edge styles, and what each does to the silhouette

The Cut style control offers three edges. The difference between them is mechanical rather than cosmetic — each one changes how the outline is built, not just how it is coloured.

• Torn (the default) runs the full noise stack at full gain. The outline wanders at all three wavelengths and carries the per-sample jitter, so it is the most irregular of the three.
• Deckle drops the shorter breaks and keeps only the long swell, and runs it at half gain. The result is the gentler edge a paper mill leaves on a sheet: fewer sharp teeth, a softer line, a shape that still reads as a cut edge rather than a tear.
• Shredded runs at 0.9 gain and adds a second, coarser tooth on top of the first. The silhouette comes out visibly rougher than Torn at the same Edge thickness and Tear intensity — closer to a torn-into-strips profile.

When a fold is the better choice instead

Reach for a fold when the point is the page rather than the picture: a poster unrolling, a card opening, a newspaper page turning. The motion carries it, and a torn edge layered on top would only fight the crease.

Reach for a torn edge when the point is that the image came from somewhere: a clipping, a ransom-note scrap, a photo ripped off a wall.

If the fold is what you actually need, this tool is the wrong one. It renders a flat silhouette and has nothing to bend, so no setting here will get you there. Use a tool that models the sheet in three dimensions, or an editor with a fold preset, and bring the torn cutout in afterwards if you want both.

Choosing between them, in one line

Torn edge: the shape is the message — clippings, scraps, collage. Fold: the bend is the message — pages, cards, reveals. If you need both, they stack cleanly in an editor, because a torn cutout is just a piece you can lay on a page that something else is turning.