What a mask actually does
A mask answers where an adjustment is allowed to act. The adjustment answers what happens there. A fully selected area receives the whole correction; a protected area receives none; a soft edge receives a proportion in between. A neutral mask can have a clearly visible overlay while leaving the photograph unchanged until you change Colour, Tone or Detail.
A local adjustment can contain several shapes and pixel-value ranges. They share one set of correction sliders. Create separate locals when you want different corrections: for example, one to warm skin and another to darken the background. Rename them by purpose, such as “Skin warmth” or “Window light”, so History is understandable later.
Choose a mask type
| Selection | What it actually selects | Good starting use | What to watch |
|---|---|---|---|
| Radial | An ellipse with a soft boundary | Gently brighten a face, food or a pool of light | It does not recognise the subject's outline. |
| Gradient | A graduated transition across a line | Darken a sky or balance one side of a room | Buildings and trees crossing that line are included too. |
| Brush | Exactly the path you paint, with width, hardness and flow | Dodge and burn irregular patches | It does not find edges or recognise objects. |
| Pen | A closed outline made of editable points and curves | A product, garment, wall or a carefully traced face | Finish the path before it affects the image. |
| Colour Range | Pixels similar to a sampled colour | Skin, foliage, a painted object or fabric | Similar colours elsewhere are selected too. |
| Luminance, Hue and Colour bands | Pixels passing one or more value limits | Keep a correction out of shadows or low-colour areas | A range is a pixel test, not an object detector. |
| AI object mask | A suggested object outline from clicks, a box or AI brush | Quickly isolate a recognisable object | Inspect the outline; fine hair and transparency are not preserved as a matte. |
| External image mask | White, grey and black values in an aligned image | Restrict a supported global tool with a mask made elsewhere | It is a separate workflow and requires the managed mask file. |
AI brush, ordinary Brush and Paint are different tools. AI brush asks the model to find an object from your stroke. Ordinary Brush paints an editable local shape. Paint inside the AI panel modifies the draft selection exactly where you paint; accepting that draft converts it to paths.
A dependable first workflow
- Correct the photograph's overall exposure and white balance first, so local changes solve a specific remaining problem.
- Open Develop → Masks. Choose the simplest selection that fits the job.
- Turn on Preview selection. Place or refine the selection before making a strong correction.
- Open Colour, Tone or Detail. Start with one modest adjustment and inspect the actual image with the overlay hidden.
- Check the edge at 100% and the overall balance at Fit. Refine coverage if the correction spills onto something else.
- Bypass the local with its eye switch for a fair comparison. If the effect is too strong, reduce the correction; a display overlay is not a strength control.
- Name the local and keep editing. Shapes, correction values and history are saved with the edit and apply on export.
The six folding sections
One section opens at a time. Opening a different section changes which controls you see; it does not disable the others.
| Section | Job | Main controls |
|---|---|---|
| Colour range | Decide which pixel colours or brightnesses qualify | Sample colour, Range width, Softness, individual Luminance/Hue/Colour bands |
| Colour | Change the selected colours | Wheel, Saturation, Lightness; further Hue shift, Warmth, Tint and Vibrance |
| Tone | Change brightness and tonal separation inside the mask | Exposure, Black, Contrast, Highlights and Shadows |
| Detail | Change texture and local fine detail | Clarity, Sharpness and Colour moiré radius |
| Shapes & overlay | Place, combine and edit shapes; inspect coverage | Shape list, Add/Intersect/Subtract/Exclude, inversion, opacity, drawing controls and overlay |
| Edge refinement | Reshape the finished selection boundary | Blur, Refine edge, Follow, Mask contrast and Mask brightness |
What each local adjustment changes
| Control | Visible effect | Practical starting use |
|---|---|---|
| Colour wheel | Adds a colour push in the direction of the puck; distance controls its strength | A small warm push for skin or a cool push for a shadow |
| Saturation | Strengthens or weakens the colours already present | Give pale skin or fabric more colour without changing its basic hue |
| Lightness | Makes selected colours lighter or darker | Lift a colour without making a large exposure correction |
| Hue shift | Rotates the existing colours around the hue wheel | Correct a specific fabric or foliage hue |
| Warmth | Moves the local colour towards cooler or warmer | The horizontal component of the same wheel correction |
| Tint | Moves the local colour towards green or magenta | The other component of the wheel; correct a local green cast |
| Vibrance | Gives muted colours more emphasis than already strong colours | A gentler increase in mixed colour intensity |
| Exposure | Brightens or darkens the selected area in stops; +1 EV doubles light | Lift a face or darken a window |
| Black | Moves the selected area's black level | Adjust the depth of the darkest selected tones |
| Contrast | Increases or reduces tonal separation | Add definition or soften harsh local contrast |
| Highlights | Adjusts the brighter selected tones | Restrain a bright forehead without darkening all skin |
| Shadows | Adjusts the darker selected tones | Lift the shaded side of a face |
| Clarity | Strengthens or softens local texture contrast | Add definition to an object; use negative values cautiously on skin |
| Sharpness | Emphasises fine edges within the mask | Add local crispness; inspect for halos at 100% |
| Colour moiré radius | Suppresses false coloured patterns over a chosen spatial size | Treat interference patterns in fabric; larger radii cover broader patterns |
Warmth and Tint stay synchronised with the wheel. They are local corrections, independent of the photograph's white balance. The wheel uses a gentle range; the numerical controls allow stronger changes. A strong correction can expose a poor selection, so repair coverage before trying to hide its edge with more blur.
Display, bypass, reset and delete
Preview selection shows coverage. Hide mask hides outlines, editable points and the colour overlay together; the correction keeps working. Show mask restores the previous display. Starting a drawing tool makes the mask visible again. Tap M to switch coverage, or hold it for a temporary look and release to restore the previous state.
Overlay strength and colour change only the diagnostic display. Shape Opacity changes actual coverage. The local's eye bypasses every correction under that mask; a shape's eye bypasses just that shape. These are different from hiding the overlay.
Reset this local's sliders restores its correction controls while retaining the selection. The bin removes the local and its adjustments. Use Ctrl+Z to undo an edit, including a completed shape drag; clicking a handle without moving it makes no change. See combining and copying masks for shape operations and transferring a local.
If the result is unexpected
- The blue or coloured selection appears, but the photo does not change: the mask may still be neutral. Adjust a local slider, then hide the overlay.
- Nothing seems selected: check the active local, its eye, shape bypass, inversion and any enabled ranges. A tight range intersected with a shape can select almost nothing.
- The wrong area changes: confirm the local and shape selected in the list. Preview coverage before moving sliders.
- An edge glows or looks cut out: reduce the correction first, then adjust feathering or edge refinement. Check at both Fit and 100%.
- The copied mask misses the subject: shapes use frame-relative coordinates, not object tracking. Reposition them on each different composition.