How to remove blemishes from photos one at a time

Heal, clone and generative fill are three different things

Every app offers one or more of these and they behave differently enough that picking the wrong one is most of what goes wrong.

Healing samples an area of nearby skin, then blends the texture from that source with the colour and brightness of the place you are covering. That blending is why it works on a cheek: the patch inherits the local tone, so it does not leave a pale disc. It is also why it fails near a boundary, because it happily blends the dark of an eyebrow into the light of a forehead.

Cloning copies pixels exactly, with no blending. It is worse on open skin, where the brightness of the source rarely matches the target, and much better along an edge such as a jawline, a nostril or the border of a lip, where you need the structure carried over intact.

Generative or content-aware fill, which is what Apple's Clean Up and Photoshop's newer removal tools use, invents plausible pixels. On a plain cheek it is excellent and instant. Near an eye, an eyebrow or the corner of a mouth it can quietly redraw anatomy, so check those results at full size rather than trusting them.

The method, spot by spot

The whole procedure takes about fifteen seconds per mark once you have done it twice.

Zoom in properly. Get the mark filling roughly a third of the screen. Working zoomed out is how people end up healing a patch four times larger than the thing they were removing.

Size the brush just over the mark. Slightly larger than the spot, not comfortably larger. A big brush drags in skin from areas with different pore size and different brightness.

Tap, do not drag. A single tap gives the tool a clean job. Dragging turns it into a smear, and smears are far harder to undo convincingly than a failed tap.

Sample from matching skin. Where the app lets you choose the source, pick skin from the same region and the same brightness. Forehead pores are larger and more directional than cheek pores, and a forehead patch on a cheek shows.

Never heal across a boundary. If a mark sits on the edge of the jaw, the hairline or a lip, heal up to the edge from the skin side only, and use a clone tool for the rest. Healing across an edge produces the soft grey blur that gives away a retouched photo instantly.

Undo immediately if it is wrong. Do not try to heal a bad heal.

Which tool in which app

For most people it is Snapseed, because the tool is genuinely good, it costs nothing, and the work is done before a subscription screen would have appeared.

Why a healed spot still looks healed

Heal a mark and zoom in, and you will often find a small island of skin with no pores in it sitting inside skin that has pores. The mark is gone and the retouch is visible, which is the worst of both.

Three fixes, in order of how often they are the right one.

Take the redness out instead of the mark. Most of what you notice about a blemish is colour, not relief. Brush the area with saturation down a few points and luminance up very slightly, or drop the red channel in the colour mixer, and a surprising amount of it disappears while the texture stays completely intact. This is the single most underused technique on this page and it is reversible.

Leave a trace. Where the app has a strength or opacity control, back it off so a faint version of the mark survives. A faint mark reads as skin. A perfectly blank patch reads as editing.

Put grain back. If the island still shows, add a small amount of grain across the whole image, not just the patch. Matching noise across the frame hides a healed area more effectively than any further work on the area itself.

What to remove and what to leave

A simple rule handles nearly every case: remove what was not there a month ago, keep what was.

Fair game, because it is temporary and it is not you: a spot, a cold sore, a scratch, a stray hair stuck to a cheek, a smear of mascara, a plaster, food on a lip, glare bouncing off glasses, a price label on a jumper.

Leave alone: moles, birthmarks, freckles, scars, acne scarring, fine lines, rosacea, vitiligo, the shape of anything. These are not blemishes, whatever a beauty app's tooltip calls them, and removing them produces a photo of somebody adjacent to you. There is also a practical argument: people who know you notice a missing mole faster than they notice a spot.

One more, and it comes up more often than it should. Do not retouch someone else's face without asking them. Removing a friend's spot before you post a group photo feels helpful and lands as a comment on their skin. Crop, choose a different frame, or ask.

Fewer marks in the frame to begin with

A raised blemish is visible mostly because of the shadow it casts, not because of its colour, which means the light decides how much editing you will be doing later.

Big, close, soft light flattens it. A window on a grey day wraps around a small bump and leaves it almost no shadow. Direct flash at close range and hard side light do the opposite, carving every bit of relief on the face into sharp contrast. If you are photographing someone who has said they are self-conscious about their skin, this one choice does more than any app.

Frontal beats side. Light coming from roughly where the camera is fills the shadow the bump would throw. It is less dramatic and much kinder.

Distance shrinks everything. A face shot on a 2x lens from two metres renders skin detail at a smaller scale than the same face at arm's length on a wide lens, so a mark simply occupies fewer pixels.

All three are free, they apply to every photo in the set rather than one at a time, and none of them has to be undone later.