Retouch

The Retouch button in the Editor header opens a side-by-side editor where the left panel shows one of your original source frames and the right panel is the stacked result you’re editing. You paint with the brush and the pixels under your cursor get replaced by the matching pixels from the source frame.

The source frame isn’t shown raw. Before it reaches the left pane it’s matched to the result — warped into alignment with the stack, put through the result’s current Look, and matched to the result’s mean brightness, its flat-region noise floor, and its camera-brightness anchor. That’s why painted pixels blend into their surroundings instead of reading as a brighter, sharper, or grainier patch. It’s also why changing the Look throws away already-loaded frames: they have to be re-matched to the new look before they’re usable again.

Renamed: this tool was called Source Cloning before. (The name Retouch previously belonged to the dust-and-blemish brush, which is now called Spot Correct.)

It’s designed for moments where the focus stacker softened a fine detail that’s perfectly sharp in one of the original frames — the classic case is a thin antenna or hair that got blurred when the blender merged in a defocused frame.

What it does

Focus stacking blends pixels from many frames. For most of the image that’s exactly what you want: it builds a single all-in-focus result from a series of differently-focused captures. But occasionally a thin feature (a moth’s antenna, a fly’s hair, a translucent wing edge) ends up softer in the blended result than it was in the one frame where it happened to be perfectly in focus.

Retouch lets you grab those pixels back. You pick the source frame that has the sharpest version of the feature, and paint that single frame’s pixels into the result. Everything else stays as the blended stack.

Strokes are editable inside the editor — undo, redo, switch source frames, paint more. Apply bakes the painted pixels into the result, and records one step per applied stroke on the image’s edit history. So Apply isn’t a point of no return: ⌘Z / Ctrl+Z outside the editor walks your strokes back one at a time, and each one shows as its own row in the HISTORY timeline.

The one limit: the editor keeps the last 30 strokes’ pixels. If a single session ran longer than that, the strokes beyond the limit collapse into one row you can’t step past — the floor of what’s undoable for that session.

When to use it

Common cases:

Thin antennae softened by the blend — moths, mosquitoes, leafhoppers, wasps.
Translucent wing edges where the blender wasn’t sure whether the pixel belonged to the in-focus subject or the out-of-focus background.
Stray hairs on insect legs or thoraxes that came out crisp in one frame and smudged in the blend.
A single petal edge that’s sharper in frame 12 than in the merged result.

Retouch is not a general-purpose spot-correction or denoise tool. For dust spots and small blemishes, use Spot Correct instead.

How to access

Retouch is enabled once a stack has finished and the per-frame alignment data is available (i.e. any multi-frame stack from Macro Studio v2026.5.27 or later — older stacks won’t have the data on disk).

Click Retouch [T] in the Editor header.
Or press T while in the Editor (and not already in another sub-mode).

If the button is greyed out, the current result is a single-frame edit, or it was produced by an older app version that didn’t cache the per-frame warps.

When the source frames have moved

Retouch reads pixels from your original frames on disk, so it needs to find them. If you reopen a saved DNG and the frames have been moved, renamed, or are on a drive that isn’t connected, the button stays enabled, and its tooltip changes to “Source frames not found — click to locate them and enable Retouch”.

Click it and Macro Studio walks you through re-pointing it at them:

It explains that the frames couldn’t be found and asks whether you want to locate them.
You pick the folder that now contains them.
It re-matches the frames by filename and, if it finds all of them, reconnects the result and drops you straight into the Retouch editor.

If only some turn up, you get a count of how many were found and a list of what’s still missing. Retouch needs all of the frames, so it stops there rather than opening with gaps. Point it at the right folder and try again.

Relocating also restores the Look slider on that image — it needs the same frames to rebuild the blend.

The editor layout

The editor takes over the center canvas with five regions, top to bottom:

Source pane on the left — the matched source frame you’re sampling from.
Result pane on the right — the stacked image you’re painting into.
Status line between the panes and the toolbar — shows “Loading source frame…” while a frame decodes. If a stack is running at the same time, it shows an amber performance warning instead, since the two compete for the same CPU and memory.
Toolbar below that — frame navigation, brush controls, Undo/Redo, the Preview in brush, Match tone and Adjustments checkboxes, Cancel, Apply.
Source filmstrip along the bottom — a thumbnail of every source frame. The bottom strip (normally your session’s results) switches to this filmstrip while you’re in Retouch, then switches back when you leave.

The right-hand panel (LOOK, MASKS, ADJUSTMENTS and the rest) hides while you’re in Retouch and comes back at its previous width when you leave. Its controls are all disabled during a Retouch session anyway, so the space goes to the two panes instead. The other full-canvas tools — Crop, Spot Correct, Defringe and the mask Brush — do the same.

The two panes sit either side of a draggable splitter — grab the divider between them to give one side more room. They start at an even split. Double-click the divider to hide the source pane entirely and give the whole canvas to the result; double-click again to bring it back. Dragging it all the way to one edge does the same thing, and the divider stays there so you can always pull the pane back out.

The panes are pan/zoom-synced: when you scroll-zoom or drag-pan one, the other follows so your brush always points at the same pixel on both sides.

Retouch opens on the view you were already looking at. If you’d zoomed in on a wing in the Editor, both panes open on that wing at the same zoom level rather than backing out to whole-image fit, so you don’t have to find your spot again. The panes are a different shape from the full Editor canvas, so the framing around it won’t match exactly, and a spot right up against an edge of the picture can sit further from the middle of a pane than it did on the canvas.

Each pane carries its own zoom readout in its bottom-left corner — click it to pick a magnification directly. The two can show different percentages, and that is correct rather than a sync bug: drag the splitter off centre and the same image fills a narrower pane on one side, so it really is being shown smaller there. A plain click on the readout never paints, and the modifier gestures — ⌥/Alt to position a source, Shift to start a line — still work over it.

While Show cursor coordinates is on (Preferences → General — it is by default), each pane also shows the pixel under your pointer beside its zoom readout — the same numbers, in the same pixel space, as the Editor canvas. There’s no right-click Copy coordinates here, because right-drag is one of the ways you pan these panes; read the numbers off the pill, or copy them from the Editor canvas instead.

Picking a source frame

The toolbar’s left/right arrows step through the source frames one at a time. The label reads Frame 12 of 40 — DSC_0451.NEF — position in the stack plus the frame’s filename, so you can tell which capture you’re looking at. You can also use the left and right arrow keys while the editor has focus.

The fastest way to get around is the source filmstrip along the bottom: click any thumbnail to jump straight to that frame instead of stepping one at a time. The strip highlights the current frame and stays in sync with the toolbar — step with the arrows or buttons and the highlight moves to match. The highlight walks all the way to the edge of the strip before the strip itself starts moving, and then advances one thumbnail per step. Each thumbnail also carries a small load badge showing whether that frame is already held in memory, currently loading, or neither — so you can see at a glance what the strip is working on. A frame with no badge is not necessarily slow: once it has been saved to disk (below) it opens straight away too. The thumbnails themselves are quick embedded previews, so the strip stays responsive even on a long stack; the big Source pane still loads the full matched frame when you land on it.

Frames load asynchronously — when you step to a frame that hasn’t been prepared yet, the source pane shows a brief “Loading…” state. Preparing a frame is real work: it is matched to the result’s look, brightness and grain so that painted-in pixels are indistinguishable from their surroundings. Three things keep the wait rare without eating your memory:

Each frame is prepared once, then saved to disk. The finished frame is written beside the stack’s other working files, so every later visit is a quick read rather than the whole job again. Changing the Look re-does them, since the match is what changed. Each frame still has to be prepared once, so the first trip through a stack is slower than the second.
The rest of the stack is prepared in the background. After a stack finishes, Macro Studio works through the remaining frames while you’re in Develop, and carries on while Retouch is open — one at a time, and it stands aside whenever you’re waiting on a frame, a stack is running, or the Editor is mid-render. So the more time you spend on a stack, the more of it opens instantly.
A cache in memory sized to your free RAM. Macro Studio measures available memory on entry and sizes the cache to fit within it, never exceeding the number of frames in the stack. Frames either side of your current position are loaded ahead of you and re-centre as you navigate. On a tight machine the cache shrinks rather than pushing you into swap.

You don’t configure any of this. The main thing it means in practice: go straight from stacking into Retouch and the first few frames still take a moment, but the longer a stack has been open, the more of it is ready.

Pick the frame where the feature you want is sharpest. Step around until the source pane shows what you want to see in the result.

Hold S to see the selected source frame full-size in the result pane, and let go to snap back. It keeps following the selection, so you can hold S and step frames — arrow keys, ⇧ + scroll, or a filmstrip click — to flip between candidates at full size instead of judging them in the narrower source pane. Painting is paused while it’s held, since you’re looking at the source rather than at what you’d be editing.

Find focus (`F`)

On a 200-frame stack, hunting for the right frame by hand is the slow part. Point the brush at the spot you want to fix and press F instead: the source pane jumps straight to the frame that’s in focus there.

On all but the smallest brushes, the cursor has a small dot in its middle. That dot is the spot F asks about — the ring shows how wide the brush is, but the question is about the one point at its centre. On a brush that’s only a few pixels across on screen the dot is left off, because it would fill the ring; the ring itself is then the mark. Zooming in grows the ring and brings the dot back.

The line under the source pane tells you which of three answers you got:

Sharpest here: frame 42 — the spot has detail of its own, and frame 42 is where that detail is in focus.
Nearest sharp detail: frame 42 — the spot is smooth background, which is out of focus in every frame, so there is no “sharpest” frame for it. Macro Studio answers with the frame that the closest sharp edge came from instead.
No sharp detail found near this spot (even if it may appear sharp) — nothing close enough has detail for Macro Studio to rank the frames by, so there is no honest answer and it doesn’t invent one.

That second answer is the useful one more often than it sounds. The usual reason to retouch background is a faint halo or glow hugging a hair, an antenna or a stem. The frame where that hair is sharp is also the frame whose background around it is clean — in that frame the hair isn’t casting a defocused smear over its own surroundings — so it’s the right frame to paint from.

A few things worth knowing:

It survives saving. The focus information is measured while the stack is built, and it’s written into the saved DNG along with everything else Retouch needs, so F still works when you reopen the file. Not every file has it, though: one saved by an older version of Macro Studio won’t, and neither will a stack that produced no focus information in the first place. F then says No focus data for this image., and the arrows, filmstrip and S all still work.
It looks for detail at several sizes. Fine grain, and broader shapes like the curve of a cap or the edge of a petal. That matters because a smooth subject can be perfectly sharp and still have almost no fine grain to compare frames by — the answer is in its larger shapes instead. Looking at both is why F can answer over a plain mushroom cap, not only over a hair.
A spot that looks sharp can still have no answer. “Sharp” to your eye means nothing looks blurry. The question F asks is which frame holds the most detail here — and a flat, even patch with no shape or texture at any size, like an out-of-focus wash, may have almost none in any frame. When that’s true of the whole neighbourhood, F says so. Point somewhere with a shape, an edge or a hair nearby and it will answer.
Some stacks have less to go on than others. A very low-contrast subject can leave parts of the frame with nothing to rank the frames by, and F will decline there. That is not the same as it being broken — it’s the tool declining to guess. It still answers where there is something to go on, which is where you are most likely to be repairing.
It works on this stack’s own frames. With the strip switched to Editor images, F says so instead of naming a frame you aren’t looking at.
Nothing is committed. F only changes which frame the source pane shows — exactly like clicking a filmstrip thumbnail. If you don’t like the frame it picked, step away from it.

When part of a frame is shaded

On a deep stack the frames at the far ends often don’t cover the whole picture once they’re lined up with the rest. It’s normal, and it’s a lens thing: as the focus travels, the magnification drifts slightly, so the first and last frames are framed a little wider or tighter than the middle one. Line them up and their edges fall short.

Macro Studio shades the parts the current frame doesn’t reach — a dark wash with a diagonal hatch over it. It appears on the source pane, and on the result pane too while you hold S to see the source frame full-size, because that’s the same frame. The result pane’s own image is never shaded: those pixels are the finished stack, and they’re fine.

If you’ve collapsed the source pane (double-click the divider), there’s nowhere for the shading to show — the refusal and the reminder line above the toolbar are then your only signs of it. Hold S, or bring the pane back, to see where the frame stops.

The brush refuses to clone from the shaded area. You paint on the result pane, so that’s where you’ll meet the refusal: the two panes are locked to the same pixel, so move the brush to the spot that lines up with the shading on the left and the cursor turns to a “not allowed” sign. Click and nothing is painted.

Nothing is wrong with your image. The stacked result on the right is complete: the stack fills those areas from the frames that do reach them. It’s this one source frame that stops short, and what sits behind the hatch is its own edge pixels repeated outwards to fill the gap, not photo. Cloning from there would smear those repeated pixels into your result — which is exactly what the shading is there to stop.

Step towards the middle of the stack and the shaded area shrinks or disappears. The middle frame is the one every other frame is aligned to, so it always covers the whole picture. When the frame on screen does have a shaded area, the reminder line above the toolbar adds Shaded: not covered by this frame; on a stack whose frames all reach the edges, it never appears.

Painting

Once the source frame looks right:

Set the Size slider in the toolbar to roughly match the feature you’re painting in (a few pixels wider than the feature is usually right — too wide and you’ll overwrite nearby blend pixels that were already correct).
Optionally adjust Feather and Strength. Feather adds a soft band outside the brush circle — the circle itself always clones at full strength, and raising Feather widens the fade beyond it rather than hollowing the circle out. Strength is the opacity a stroke reaches: at 100% one pass clones outright, and lower values blend the source in, so a repair can be eased in gently.
Click or drag on the result pane (right side). The pixels under your brush get replaced by the corresponding pixels from the source pane.

Tick Preview in brush (in the toolbar, next to Undo/Redo) to fill the brush circle with the source frame as you hover, so you can see what a stroke would clone in before you commit to it. The preview is weighted by Feather and Strength — it shows what a stroke actually leaves behind, soft at the edge and only as opaque as the Strength setting, rather than an idealised full-strength cut-out. At a low Strength that means the preview is faint, because that’s what the stroke does. It follows Match tone too, so what you see in the circle is what lands.

It pauses while you’re actually painting, so the circle shows the real result rather than previewing a second pass over pixels the stroke has already finished with. It comes back as soon as you lift the mouse.

Macro Studio remembers the setting between sessions.

Painting in straight lines

Some of what you’ll paint out is straight: an antenna, a leg, the edge of a wing case, a stray hair across the frame. Freehand-dragging along one and keeping it steady is fiddly, and two ordinary clicks at either end just leave two dots with a gap between them.

Hold Shift and click twice instead:

Shift-click one end. Nothing is painted yet — a marker shows where the line will start.
Move the mouse. A band follows the pointer, at the width your brush will actually paint. This is the line you’re about to lay down, so you can line it up against the feature before committing to it.
Shift-click the other end. The whole segment is painted in one stroke.

Let go of Shift at any point in between and the line is abandoned — nothing is painted and the marker disappears. That’s the way out if you change your mind, so a half-composed line is never something you have to remember to clean up.

A few things worth knowing:

The line is one stroke. A single Undo takes back the whole thing, not the last dab.
It paints exactly like a drag along the same line — same Size, Feather, Strength and Match tone as any other stroke.
The preview shows what will land, not just where. With Preview in brush off, the marker and band are pale blue. Tick it and they fill with the source frame instead — tone-matched, if Match tone is on — so you can see the repair itself before you commit. Either way the band carries the brush’s real shape: solid across the middle, fading out through the soft edge exactly as the stroke will, with a dashed outline marking how far that edge reaches. At Feather 0 there’s no soft edge to show, so the band stops at the brush and the dashed outline isn’t drawn. With Preview in brush on the band also dims with Strength, since that’s what a partial-strength stroke leaves; the plain blue stays fully visible whatever your Strength, because its job is to show you where the line goes.
Each line is its own two clicks. Painting one clears the start point, so tracing a bent feature means clicking the joint twice: Shift-click A, Shift-click B to paint A→B, then Shift-click B again to start the next leg and C to paint it.
Anything that takes the canvas away abandons the line. Holding S to check the source frame does, and so does switching away from the app — in both cases nothing is painted and you start the line again.

Match tone

A source frame is matched to the stacked result before you paint it in — the same sharpening and contrast, the same overall brightness, the same grain. But those are whole-frame corrections, and they can leave a local difference behind. The patch arrives with exactly the right detail and slightly the wrong brightness, so it reads as a lighter or darker square against its surroundings. It shows up most on a smooth out-of-focus background, which is where a patch has nothing to hide behind.

Match tone (in the toolbar) fixes that. It keeps the source frame’s detail but takes the brightness and colour of whatever surrounds your brush, so the patch blends into the background instead of sitting on top of it. On a typical stack this is the difference between a clearly visible step at the brush edge and one you cannot find.

It also handles blend halos — the bright or dark rim that sometimes follows a high-contrast edge like an antenna. Painting over one with Match tone on replaces it just as cleanly as plain cloning does.

Tick Match tone when a patch is showing as a lighter or darker square — most obviously on a smooth out-of-focus background — and leave it on for as long as you are working on that kind of repair. It’s remembered between sessions, so it’s a choice you make once.

Fresh installs start with it off, and if you’ve been using Macro Studio since before this note you keep it on until you untick it yourself. Tone matching used to be much more expensive than it is now — the brightness map is built once for each stroke instead of continuously as you drag, so on a large stack it costs about two-thirds again on top of a plain clone rather than several times over. Speed is no longer much of a reason to leave it off; the reason below is.

If the brush ever does feel heavy — with or without Match tone — zoom in. It lays its dabs at a spacing measured in image pixels, so a drag across a zoomed-out view covers far more ground per moment than the same drag zoomed in, and does proportionally more work. A slower drag helps for the same reason.

When you don’t want it. Match tone reproduces the brightness it finds, faithfully. So it cannot paint out a defect that is purely a brightness problem — a dark blotch with no texture difference stays exactly where it is, because the tone under your brush is the tone it copies. If what you are trying to remove is the tone itself rather than the detail, leave Match tone unticked and the brush clones outright.

Preview in brush, Match tone and Adjustments each have a keyboard shortcut — P, M and A — and all three are remappable. The key shown in brackets on each label follows whatever you set.

Macro Studio remembers this setting between sessions, and each stroke records how it was painted — so reopening a saved DNG replays your tone-matched strokes as tone-matched, and strokes from before this feature existed exactly as they were.

You can switch source frames mid-edit. Strokes from earlier frames stay baked into the working copy; the next stroke samples from whichever frame is currently shown on the left.

Your adjustments while you retouch

Both panes show the image with your Adjustments applied — your exposure, white balance, contrast and any Subject, Background, Brush or gradient mask work. So you are retouching the picture you are going to save, not the flat stack underneath it.

This matters most for the source pane. Deciding whether a patch will match is the main thing you do in this editor, and you cannot judge it against a source frame that is showing different tone from the result beside it. Source frames are already lined up with the result, so they take the same masks you dialled in — the subject mask lands on the subject in both panes.

Your strokes still paint on the raw pixels underneath. Adjustments are non-destructive: they sit on top of the image and are applied again every time it is drawn or saved. So Retouch shows you the adjusted picture but paints the plain one, and your sliders keep working normally afterwards. Nothing is baked in twice.

Untick Adjustments in the toolbar — or press A — to drop back to the raw pixels. Two reasons you might: to judge cloned detail without a strong Clarity or Sharpness setting flattering or spoiling it, and to speed the panes up on a slow machine if you have a lot dialled in. The setting is remembered between sessions, and Spot Correct and Defringe each keep their own.

A note on sharpness. With Adjustments on, the panes redraw at a reduced size first and then sharpen up the part you are looking at a moment later — the same thing the main Editor canvas does when you pan or zoom. You will see it as a brief softness right after a zoom or a pan, never while painting. With Adjustments off, or with nothing dialled in, the panes are always at full resolution and there is nothing to wait for.

Cloning from another Editor image

Sometimes the pixels you want aren’t in this stack at all — they’re in another one. The usual case is that you stacked the same shot twice and the second run got something right that the first didn’t. Rather than choosing between the two results, you can paint the good part of one into the other.

The two buttons at the left of the bottom strip switch which set of images you’re sampling from:

Source frames — this stack’s own frames. The default, and everything above.
Editor images — the other stacks in this session, the same ones the history strip shows, in the same left-to-right order. Greyed out until there is at least one. Switching to it lands on your most recent stack.

Click a thumbnail to start cloning from that image. Everything else works exactly as it does with a source frame: paint on the right pane, the left pane shows what you’re sampling, and Preview in brush and Match tone both apply.

Lining the two images up

If both results came from the same frames, they line up automatically — no positioning needed. Macro Studio can tell from the two stacks’ own alignment data that they occupy the same coordinates, so a pixel in one is the same point on the subject as in the other. The frame label says aligned to this stack when this has happened. Re-stacking a folder with a different Look, or different blend settings, always lands here.

Anything else — a different capture, or the same photos stacked from a different selection of frames — has no such guarantee, so the image is laid over the top and you line it up yourself. An amber bar across the top says your images need to be aligned, and a note beside the strip buttons tells you what to do next as you go. The bar clears the moment you’ve positioned the image; until then, anything you paint lands in the wrong place.

Lining it up is two clicks — this feature goes here:

Alt-click (⌥-click on Mac) a recognisable feature in the source pane, on the left. An amber crosshair marks it.
Alt-click the same feature in the result pane, on the right.

The source slides so those two points meet, and the note turns grey: Positioned — repeat to refine — with the same two-click instruction after it, so you don’t have to remember it. Do it again as often as you like; a rough first attempt costs nothing. Any part of the result with no source behind it simply won’t paint.

The same two clicks work on an automatically-aligned image if you want to shift it deliberately — the note warns you before the second click that it will replace the automatic alignment. Re-picking the image from the strip puts the automatic alignment back.

Pick something small and unambiguous for the two clicks — the tip of an antenna, a highlight on a hair — rather than a broad area. The alignment is exactly as accurate as your two clicks are.

Images are used at their native pixel scale; nothing is resized to fit. Two stacks shot at different magnifications will not line up under this, and that’s a real limit rather than something to work around with the anchor.

Letting Macro Studio finish the job

Next to the strip buttons there’s an Align automatically button. It compares the two images and nudges the source the rest of the way, so you don’t have to be precise with the two clicks.

It works best as a finisher, not a starter. Get the image roughly in place first — one pass of the two clicks is plenty — then press it. Working from something close is what lets it lock on; from a cold start, two images that are a long way apart usually can’t be matched.

It tells you when it can’t. Two images that aren’t the same subject, or don’t overlap enough, will come back with couldn’t align these automatically and the image stays exactly where it was. That’s the intended behaviour, not a failure: a wrong alignment isn’t visible until you paint and see smeared pixels, so it would rather admit defeat than guess. Position it by hand, or get it closer and press again.

Differences in brightness and contrast don’t bother it, so two runs of one stack at different Looks match fine. Differences in scale or rotation are beyond it — same limit as the manual anchor.

The button doesn’t appear for images that lined up automatically. Those are already exact, and an estimate could only make them worse.

How it’s saved

A stroke from one of this stack’s own frames is recorded as “frame 3, this path, this brush” — the frame is on disk, so Macro Studio can re-read it whenever it needs to re-render. An Editor image isn’t one of those frames, and it may not exist on disk at all.

So the DNG carries the pixels instead. When you Apply, the part of the Editor image your strokes actually sampled is cropped out and stored inside the DNG itself, next to the strokes. That keeps the file self-contained: it survives quitting, moving the file, copying it to another machine. There’s nothing to keep alongside it and nothing to relocate later.

Only the sampled region is stored, so the cost is proportional to how much you painted — normally a few hundred KB. The Natural / Enhanced toggle keeps working, and reopening the DNG reproduces the strokes.

If you paint from an Editor image across a very large area, the stored region can outgrow the space reserved for it. Those strokes still apply — the pixels are real and Apply bakes them in — but they can no longer be reproduced, so the Look toggle switches off for that image and an amber bar tells you. Everything else is unaffected: you can save, export, and keep adjusting as usual.

Control	What it does
◀ / ▶	Step to the previous / next source frame. (Or use arrow keys.)
Frame n of m — filename	Which source frame is currently loaded on the left pane, and which file it came from. On a narrow window it shortens from the middle, keeping the frame number and the file extension.
Size	Brush radius, 2–400 image pixels, with the current value shown beside the slider. It’s the image’s own pixels, so the number stays put when you zoom — and it’s a radius, so a Size of 100 covers 200 pixels across. From the canvas: [ / ] shrink and grow it, and ⌘ + scroll / Ctrl + scroll does the same on the wheel.
Feather	Width of the soft band outside the brush circle, 0–100% (default 100%). 0% is a hard edge; 100% fades out across a second brush-width. The circle you see always clones at full strength. From the canvas: { / } step it, and ⌘⇧ + scroll / Ctrl+Shift + scroll does the same on the wheel.
Strength	Opacity a stroke reaches, 5–100% (default 100%). 100% clones at full opacity in one pass; lower values blend the source in, and painting over the same spot again builds up — useful when a repair needs easing in rather than replacing outright. From the canvas: , / . step it by 5%, ⌥⌘ + scroll / Alt+Ctrl + scroll does the same on the wheel, and 0–9 types a value straight in.
↩ / ↪	Undo / Redo. One step per stroke (gesture), not per pixel.
Preview in brush (P)	Fill the brush circle with the selected source frame, weighted by Feather and Strength, so you can see what a stroke would leave before you paint it. Pauses while you paint. Remembered between sessions.
Match tone (M)	Keep the source frame’s detail but take the brightness and colour of what surrounds the brush, so a patch does not show as a lighter or darker square. Off on fresh installs; if you were using Macro Studio before that changed, you keep it on. Leave it off to clone outright — which is what you want when the tone is the thing you are painting out. Remembered between sessions.
Adjustments (A)	Show both panes with your Adjustments applied, so you retouch the picture you will save. On by default. Your strokes are painted on the raw pixels underneath either way, so your sliders keep working afterwards. Remembered between sessions. See Your adjustments while you retouch.
Source frames / Editor images	Which set of images the brush samples from — this stack’s own frames, or another stack from this session. See Cloning from another Editor image.
Cancel	Exit the editor and discard all strokes.
Apply	Bake the painted pixels into the result, recording one edit-history step per stroke.

Keyboard + mouse reference

In the editor:

Action	Result
Left-click and drag	Paint source pixels into the result. Refused wherever the current source frame has no pixels — the cursor turns to a “not allowed” sign, at the spot matching the shaded area on the source pane.
Shift-click twice	Mark one end, then the other, and the straight segment between them is painted in one stroke. The first click only marks — a band previews the line at brush width until you commit. Releasing Shift abandons it. See Painting in straight lines.
Scroll / Pinch	Zoom centered on the cursor (synced across both panes).
⌘ + scroll / Ctrl + scroll	Resize the brush.
[ / ]	Shrink / grow the brush.
{ / }	Shrink / grow the soft band outside the brush (less / more Feather).
⌘⇧ + scroll / Ctrl+Shift + scroll	Change Feather — scroll up for softer. Shift added to the resize gesture above, the same way { / } are Shift added to [ / ].
Space + drag	Pan the canvas (synced across both panes). Spacebar is the default; the key is configurable — ⌥/Alt, Shift and ⌘/Ctrl are the alternatives. If you pick Shift, a bare Shift-click on the result pane paints a line instead; pan that pane with right-drag, or by adding a second modifier to the Shift-drag.
Right-drag or middle-drag	Pan as well, without holding a modifier.
Double-click	Reset zoom to fit.
Double-click the pane divider	Even the two panes up; double-click again to hide the source pane for a full-width result. Dragging the divider also snaps to an even split, and the grip turns blue when it is there.
Left / Right arrow	Step to previous / next source frame.
⇧ + scroll / Shift + scroll	Step through source frames without leaving the canvas.
S (hold)	Show the selected source frame in the result pane; release to go back. Abandons a half-composed Shift-click line.
F	Find focus — jump to the frame in focus at the dot in the middle of the brush. See Find focus.
Click a filmstrip thumbnail	Jump straight to that source frame.
⌥-click / Alt-click the source pane	Mark the feature to line up, when positioning an Editor image.
⌥-click / Alt-click the result pane	Mark where that feature belongs; the source slides to match. Both only while an Editor image is selected — otherwise the modifier is free for panning.
⌘Z / Ctrl+Z	Undo last stroke.
⌘⇧Z / Ctrl+Shift+Z	Redo.
Esc	Cancel.

Outside the editor, on your applied edits:

Action	Result
⌘⌥Z / Ctrl+Alt+Z	Toggle last edit — flick the step at your current position in the edit history off and on. A quick A/B of the change you just made; press again to put it back. Works on any edit, not just Retouch.

Tips

Zoom in first. Painting at fit-to-window zoom oversizes the brush. Zoom to at least 100% so the brush size you pick matches the feature you’re targeting.
Let F find the frame for you. Point at the spot and press F rather than clicking along the filmstrip — see Find focus. It’s the fastest way in on a deep stack, including just off an edge, where “which frame is sharpest” has no obvious answer by eye. Out in open background, far from anything with detail, it will tell you it has nothing to go on.
Scan frames before painting. It’s tempting to start painting from frame 0; almost always there’s a better source frame deeper in the stack. Click along the filmstrip to find the one frame where the feature is sharpest — that’s the whole point of Retouch.
Short strokes, not one long drag. Undo works per-stroke, not per-pixel — keep strokes short so a mistake is one Undo away.
Stacked it twice? Clone between the runs. If a second stack fixed one area but you prefer the first everywhere else, you don’t have to pick. Switch the strip to Editor images and paint the good part across — two runs of the same frames line up automatically.
Combine with Masks for adjustments. Painted pixels live in the same color space as the rest of the stack, so the Subject / Background masks still cover them correctly after Apply. Retouch first, then mask-and-adjust.