Fixing halos, missing parts, and rough edges in a cutout

Most cutouts are good on the first try. When one is not, the problem almost always falls into one of a handful of categories, each with its own fix. This guide is organized by symptom: find what you see, then try the fixes in order.

First, look at the result properly

Before fixing anything, make sure you are seeing the problem clearly:

• Use the compare slider to switch between original and result.
• Preview on different backgrounds. A light halo is invisible on white and obvious on black. Switch the background between white, black, and transparent (checkerboard) to check.
• Zoom in on edges, especially hair, fingers, and thin parts.

Symptom: a halo or fringe of the old background

You see a thin outline around the subject in the old background's color, most visible on a contrasting new background.

Why it happens: the mask is slightly larger than the subject, or the edge pixels are partly transparent but still contain the old background's color.

Fixes, in order:

1. Open Settings and move the edge slider toward Tighter by 1 or 2 pixels. This shrinks the mask, cutting off the outermost edge pixels. It applies instantly, without re-running the model.
2. If a halo remains only around hair, a tighter edge can also thin the hair. Instead, choose a new background closer in brightness to the original, which hides the fringe.
3. Reshoot if possible, with more contrast between subject and background, or with the subject farther from the wall (less color spill).

Symptom: missing parts

Fingers, a bag strap, a pet's tail, a cable, or the legs of a chair have disappeared.

Why it happens: thin parts cover few pixels after the image is resized for the model, or they are low-contrast against the background, so the model judges them as background.

Fixes:

1. Move the edge slider toward Wider by 2 to 4 pixels. This grows the mask, which can recover thin parts that were just barely clipped.
2. Use Select object: paint over the whole subject, including the missing part, or draw a loop around it. The model then runs again on just that region, at a larger relative size, which often recovers thin details.
3. Crop the photo closer to the subject before processing, for the same reason.
4. Try the 16-bit or 32-bit model in Settings, which can keep slightly finer detail.

Symptom: the wrong subject

The model kept the sofa and removed the person, or kept one product and removed the other.

Why it happens: the model looks for the single most prominent subject. When several objects compete, or the intended subject is small, it may choose differently than you would.

Fixes:

1. Use Select object and paint over (or loop around) only what you want to keep. This is exactly what it is for.
2. Crop to the subject you want before processing, so it is the obvious main subject.
3. For a group of separate items you want to keep together (several products, a logo made of separate pieces), paint over all of them in one selection.

Symptom: background visible through gaps

The space between an arm and the body, the inside of a handbag handle, or the hole in a letter O still shows the old background.

Why it happens: small enclosed areas are easy to miss, especially when they are similar in color to the subject.

Fixes:

1. Move the edge slider toward Tighter slightly; small gaps sometimes open up.
2. Use Select object with a careful paint stroke that avoids the gap, so the model re-evaluates the region.
3. For important work, the remaining gap can be erased by hand in a design tool after exporting a PNG; see using cutouts in design apps.

Symptom: rough, jagged, or blocky edges

The outline looks pixelated or has a staircase pattern.

Why it happens: the source image is small or heavily compressed (screenshots, images from messaging apps, old web images), so there is little real edge detail to work with.

Fixes:

1. Use the largest, least compressed original you can find. Images forwarded through messaging apps are usually compressed; ask for the original file.
2. Avoid enlarging small images. A cutout cannot add detail that was not in the original.
3. A small Tighter setting can smooth a ragged outline slightly.

Symptom: hair looks like a helmet

Hair is cut along a smooth outline and all the fine strands are gone.

Fixes: move the edge toward Wider, try a higher-precision model, and choose a new background similar in brightness to the original. For a deeper explanation, see why hair, fur, and glass are hard.

Symptom: the result is blank or nearly empty

The model found no subject, or almost none.

Fixes: this usually happens with images that have no clear main subject: landscapes, room interiors, text documents, or patterns. Crop to a single object, or use Select object to tell the tool what to keep. If it happens on an ordinary portrait or product photo with WebGPU enabled, switch back to CPU / WASM in Settings; see WebGPU vs WebAssembly.

When to stop and reshoot

If you have tried the edge slider, Select object, and a higher-quality model, and the cutout still is not good enough, the problem is usually the photo. A new photo with a plain, contrasting background and good light will cut out cleanly faster than any amount of fixing. How to shoot product photos for clean cutouts applies to portraits too.

Summary

Match the fix to the symptom: Tighter for halos, Wider for clipped parts, Select object for the wrong subject or missing pieces, a larger original for jagged edges, and a forgiving new background for difficult hair. Preview on dark and light backgrounds before downloading, and reshoot when the photo itself is the problem.