Chapter 04

Layers

Layers are like transparent sheets stacked on top of each other: each one carries part of the image, and you can move, hide, mask and blend them individually without touching the others. This chapter explains the Layers panel, the Layer menu and every kind of layer – from a simple pixel layer to a smart object with smart filters.

Layer types at a glance

Chromatelier has several kinds of layers. The thumbnail in the Layers panel tells you which kind you are looking at.

Layer type	How to recognize it	What it is for
Pixel layer	Thumbnail of its content	Painted, pasted or photographed pixels. The only kind you can paint on directly.
Group	Folder icon with an arrow to expand and collapse it	Bundles layers so you can hide, move or mask them together.
Adjustment layer	Half-circle icon with a mask next to it	A color or tonal correction that affects all layers below it and can be changed at any time.
Fill layer	Color, gradient or pattern preview with a mask next to it	An area of solid color, gradient or pattern that you can set up again at any time.
Text layer	“T” instead of a thumbnail	Editable text (see Text, Shapes & Paths).
Shape layer	Thumbnail with a vector mask	Vector shapes with fill and stroke.
Smart object	Small badge at the bottom right of the thumbnail	Embedded content that does not lose quality when scaled and can carry smart filters.
Frame	Pixel or smart object layer with a rectangular or elliptical vector mask	A placeholder you put a picture into.
Video layer	Thumbnail of the current frame	A video clip in the timeline (see Video & Animation).

The Layers panel

You show and hide the Layers panel with Window › Layers or F7. It has three parts: at the top, the properties of the active layer; in the middle, the layer list (the top row is the topmost layer in the image); and at the bottom, a bar of buttons.

Blend mode, opacity and locking

Blend mode (drop-down list at the top left, initially Normal): sets how the layer is combined with what lies below it. All modes are explained in the section Blend modes. Groups also have Pass Through.
Opacity (0–100 %): how visible the layer is, including its layer styles. Dragging the value counts as a single step in the history.
🔒 Lock pixels: protects the layer’s pixels from painting, erasing and filters. A locked layer shows a lock icon after its name.

You set the fill opacity (only the pixels, not the layer styles) in the Layer Style dialog or in the Properties panel. If several layers are selected, a change to the blend mode, opacity or lock applies to all of them.

A layer row

From left to right, each row shows:

Eye – a click hides or shows the layer. Hidden layers appear gray.
Indent – layers inside groups are indented; layers clipped to a clipping mask carry a bent arrow pointing down.
Thumbnail – a click makes the layer active; a blue frame shows that you are painting on its pixels. A double-click opens the matching dialog for the kind of layer: adjustment layer → adjustment dialog, fill layer → fill options, text layer → edit text, smart object → edit contents, group → expand and collapse, pixel layer → layer style.
Mask thumbnail and vector mask thumbnail, if there are any (see Layer masks). A red cross means the mask is disabled.
Name – double-click to rename (Return confirms, Esc cancels). The name of a layer that other layers are clipped to is underlined.
Icons – lock (locked), chain link (linked), fx (layer style; a click opens the dialog) and, if they are not Normal/100 %, the blend mode and opacity in small type.

A smart object lists its smart filters in rows of their own beneath it.

Selecting several layers

⌘-click on a row adds it to the selection or removes it.
⇧-click selects all rows between the active one and the one you click.
Select › Layers › Select All Layers (⌘ ⌥ A) selects all layers.

Selected layers have a lighter background, the active one the lightest. Many commands act on all selected layers: duplicate, delete, group, link, align, clipping mask, blend mode and opacity. When several layers are selected, Merge Down is called Merge Layers.

Reordering layers by dragging

Drag a row up or down with the mouse. A blue line shows where the layer will land. If you release it over the middle of a group, a frame appears around the group – the layer then goes inside it. You can move whole groups with their contents this way, too. Without the mouse, use Layer › Arrange › Bring Forward (⌘ ]) and Send Backward (⌘ [).

The buttons at the bottom

Button	Effect
New layer	Empty pixel layer above the active one (`⌘` `⇧` `N`).
New group	Empty group above the active layer.
Add layer mask	Mask from the current selection; without a selection, a white mask that shows everything.
Duplicate layer / group	Copy of the selected layers.
Delete layer / group	Removes the selected layers.
Move up / Move down	One step up (`⌘` `]`) or down (`⌘` `[`) in the stack.
Merge down	Merges with the layer below; for a group, merges the group (`⌘` `E`).
Flatten image	Turns all layers into a single opaque layer.
Layer style (fx)	Opens the Layer Style dialog.
New adjustment layer	Opens the list of adjustment layers.

The Layer menu

The open Layer menu — The Layer menu. Commands shown in gray do not apply to the active layer right now.

Creating new layers

The Layer › New submenu — Layer › New with layer, group, artboard, layer via copy/cut and video layer.

Command	Shortcut	Effect
New › New Layer	`⌘` `⇧` `N`	Empty, transparent pixel layer “Layer N”.
New › New Group		Empty group “Group N”.
New › New Artboard…		See Artboards.
New › Layer via Copy	`⌘` `J`	Copies the selected area of the active layer to a new layer. Without a selection, the whole layer is duplicated – a text layer stays text and a smart object stays a smart object.
New › Layer via Cut	`⌘` `⇧` `J`	Like the above, but removes the area from the original layer. Works only on pixel layers – rasterize other layers first.
New › New Video Layer from File…		Brings a video clip (MP4, M4V, MOV) into the document as a layer. More in the chapter Video & Animation.

Duplicating, deleting, sending to another document

Layer › Duplicate Layer copies all selected layers (groups with their contents).
Layer › Delete Layer removes the selected layers. You cannot delete the last layer of a document.
Layer › Duplicate to lists the other open documents; a click copies the active layer there. If only one document is open, the entry is gray. If documents are shown side by side (Window › Arrange), you can also drag a layer onto another document with the Move tool.

Layer content and rasterizing

Under Layer › Layer Content you find:

Adjustment Properties… – opens the adjustment dialog of the active adjustment layer (just like a double-click on its thumbnail).
Fill Content Options… – opens the settings of a fill layer.
Rasterize Layer – turns a smart object or a fill, text, shape or video layer into an ordinary pixel layer. You can then paint on it, but its special properties (editing text, changing the fill, lossless scaling) are gone. A video layer keeps the frame it is currently showing.

Groups

Groups keep the Layers panel tidy and can be treated like a single layer: hidden, moved, masked, and given a blend mode and opacity.

Layer › Group Layers (⌘ G) puts all selected layers into a new group.
Layer › Ungroup Layers (⌘ ⇧ G) dissolves the active group; its contents are kept.
Click the arrow in front of the folder icon to expand and collapse the group; a double-click on the folder icon does the same.
Drag layers into a group or out of it (see Reordering).

New groups have the blend mode Pass Through: the layers inside blend as if the group were not there – an adjustment layer in the group then also affects everything below it. If you set the group to Normal or another mode, its contents are first composited on their own; adjustment layers inside it then only affect the group.

Blend modes

The blend mode determines how the colors of a layer (the “top”) are combined with what is visible below it (the “bottom”). You choose it at the top of the Layers panel. You find the same list in tools, layer styles and dialogs such as Edit › Fill….

Blend mode	Effect
Normal	The top color covers the bottom one; only opacity and transparency let anything through.
Dissolve	Semi-transparent areas are shown either fully or not at all at random – a grainy transition.
Darken	In each channel, the darker value wins.
Multiply	Multiplies the colors: the result is always darker, and white changes nothing. Good for shadows and line drawings on paper.
Color Burn	Darkens strongly while increasing contrast and saturation.
Linear Burn	Darkens by reducing brightness; harsher than Multiply.
Darker Color	Shows, per pixel, whichever of the two colors is darker overall (not channel by channel).
Lighten	In each channel, the lighter value wins.
Screen	The counterpart to Multiply: the result is always lighter, and black changes nothing. Good for highlights and glows.
Color Dodge	Lightens strongly and reduces contrast; light areas blow out easily.
Linear Dodge (Add)	Adds the brightness values – stronger than Screen.
Lighter Color	Shows, per pixel, whichever of the two colors is lighter overall.
Overlay	Boosts contrast: dark areas at the bottom are multiplied, light ones are screened. 50 % gray at the top changes nothing.
Soft Light	A gentle version of Overlay, like diffuse light.
Hard Light	Like Overlay, but the top layer decides the direction – like a harsh spotlight.
Vivid Light	Combines color dodge and color burn depending on the top brightness; very strong.
Linear Light	Combines linear dodge and linear burn.
Pin Light	Replaces dark or light areas depending on the top brightness; for special effects.
Hard Mix	Each channel goes fully on or fully off – strong posterization in primary colors.
Difference	Subtracts the lighter color from the darker one. Identical image areas turn black – handy for aligning two photos.
Exclusion	Similar to Difference, but with less contrast.
Subtract	Subtracts the top color from the bottom one.
Divide	Divides the bottom color by the top one; usually lightens strongly.
Hue	Hue from the top, saturation and brightness from the bottom.
Saturation	Saturation from the top, hue and brightness from the bottom.
Color	Hue and saturation from the top, brightness from the bottom – ideal for tinting.
Luminosity	Brightness from the top, color from the bottom.

Groups also have Pass Through (see Groups).

Layer masks

A layer mask hides parts of a layer without deleting any pixels. It is a grayscale image: white reveals, black conceals, and shades of gray let the layer show through partially. You can touch up the mask at any time – which makes it the most important tool for composites.

Layers with masks, one of them disabled — Layers with masks. The top mask is disabled (red cross), the group has an elliptical mask and the “Clouds” layer a gradient mask.

The commands under Layer › Layer Mask

The Layer › Layer Mask submenu — Layer › Layer Mask. The commands in the middle become active once the layer has a mask.

Command	Effect
Remove Background	Detects the subject with a local AI model and creates a matching mask (see AI on your computer).
Reveal All	New white mask – the layer stays fully visible at first.
Hide All	New black mask – the layer is invisible at first; you paint with white to bring out what should appear.
Reveal Selection	New mask from the current selection: the selected area stays visible, the rest is hidden. The selection is removed in the process.
Disable / Enable	Temporarily switches off the mask’s effect; its thumbnail then shows a red cross.
Edit Mask ⇄ Layer (`⌘` `\`)	Switches whether brushes and filters act on the mask or on the layer’s pixels.
Load as Selection	Turns the mask into a selection.
Apply	Bakes the mask into the pixels (hidden areas become transparent) and removes it. Not available for groups.
Delete	Removes the mask without applying it.

A layer has at most one layer mask; the commands for adding one are gray as long as a mask already exists.

Editing the mask or editing the layer

The blue frame around the corresponding thumbnail shows whether you are painting on the mask or on the layer. As long as the mask is the target, the status bar at the bottom shows ◼ EDITING MASK.

Click on the mask thumbnail	Effect
Click	Edit the mask.
`⇧`-click	Disable / enable the mask.
`⌥`-click	Show the mask itself as a black-and-white image on the canvas (`⌥`-click again: back to the image).
`⌘`-click	Load the mask as a selection.

A click on the layer thumbnail switches back to editing the pixels. With adjustment and fill layers you always paint into the mask, because they have no pixels of their own.

Blending two pictures with a layer mask

Open the first photo and bring in the second one as a layer above it with File › Place Embedded… or by copying and pasting.
Select the top layer in the Layers panel and click Add layer mask at the bottom. A white mask appears next to the thumbnail; it is selected for editing right away.
Choose the Gradient tool (G), set a linear gradient in the options bar and press D for the default colors black and white.
Drag a line across the canvas through the area where the pictures should blend into each other. Where the mask turns black, the lower picture shows through. A short drag gives a hard transition, a long one a soft transition.
Touch up with the brush (B): black hides more of the top layer, white brings it back, and X swaps the colors.
Check the result with ⇧-click on the mask thumbnail (mask off and on again). The pixels of the top layer are unchanged – you can keep working on the mask at any time.

Vector masks

A vector mask limits the layer with a path instead of pixels. It stays crisp when scaled and can be reshaped with the path tools. A layer can have a vector mask in addition to its layer mask; its thumbnail sits to the right of it.

Command under Layer › Vector Mask	Effect
Reveal All	Empty vector mask that shows everything.
Hide All	Empty vector mask that hides everything.
Current Path	Turns the path selected in the Paths panel into the vector mask.
Disable / Enable	Switches the vector mask off or on.
Delete	Removes the vector mask.

A click on the vector mask thumbnail makes its path editable with the path tools; ⇧-click switches it off and on. Shape layers already have their shape as a vector mask, so these commands are not available there. More about paths in the chapter Text, Shapes & Paths.

Clipping masks

With a clipping mask, a layer is visible only where the layer directly below it (the base layer) has content. This lets you fill text with a photo, for example, or make a correction affect just one layer.

Layer › Create Clipping Mask (⌘ ⌥ G) clips the selected layers to the layer below. If the active layer is already clipped, the command is called Release Clipping Mask.
It is quicker to ⌥-click the layer’s name in the Layers panel.
Several clipped layers stacked on top of each other share the same base layer.

Layers panel with clipped layers — Clipped layers are indented and carry an arrow pointing down; the base layer’s name is underlined.

Making an adjustment layer affect just one layer

In the Layers panel, select the layer you want to correct – for example a pasted object whose colors don’t match the background.
Click New adjustment layer at the bottom and choose, for example, Hue/Saturation. The new adjustment layer sits directly above the selected layer, and its dialog is open.
Confirm the dialog with OK for now. At this point the correction still affects all layers below.
Hold down ⌥ and click the adjustment layer’s name – or choose Layer › Create Clipping Mask. The row is indented and shows the arrow pointing down.
Double-click the adjustment layer’s thumbnail and fine-tune the correction. Now only the layer below changes; the rest of the image stays as it is.

Adjustment layers

An adjustment layer contains no pixels, but a correction that affects everything below it. Unlike the commands of the same name under Image › Adjustments, it does not change the image permanently: you can change the values at any time, hide the layer, lower its opacity or limit it to parts of the image with its mask.

These 16 adjustment layers are available: Brightness/Contrast, Levels, Curves, Exposure, Vibrance, Hue/Saturation, Color Balance, Black & White, Photo Filter, Invert, Posterize, Threshold, Gradient Map (FG→BG), Channel Mixer, Selective Color and Color Lookup. What each adjustment does is explained in the chapter Adjustments.

Several adjustment layers in the Layers panel — Five adjustment layers stacked on top of each other, one of them hidden. The masks show where they take effect.

Levels dialog of an adjustment layer — A double-click on the thumbnail opens the adjustment dialog again.

Working with adjustment layers

A new adjustment layer appears above the active layer, and its dialog opens right away. The preview in the image is live.
To change it, double-click the thumbnail or choose Layer › Layer Content › Adjustment Properties….
In the Properties panel (Window › Properties) the sliders of the active adjustment layer are available directly, with the Adjustment Properties… button below them. Adjustments with their own interface (such as Curves) show the note Its settings are in its dialog there.
Painting with black into the mask takes the correction back in those areas.
Merge Down (⌘ E) bakes an adjustment layer into the pixel layer below it.

Fill layers

Fill layers are areas whose content you can set up again at any time. Like adjustment layers, they have a mask; if a selection is active, it becomes the mask, and the fill then appears only there.

Command	Settings
Layer › New Fill Layer › Solid Color…	A color from the color picker. It starts with the foreground color.
Layer › New Fill Layer › Gradient…	Color stops with positions, Style (Linear, Radial …), Angle, Scale and Reverse. It starts with foreground to background color.
Layer › New Fill Layer › Pattern…	A pattern from the pattern list and the Scale. You create your own patterns with Edit › Presets › Define Pattern….

Color fill dialog with color picker — A new solid color fill layer: the color picker opens right away.

Gradient fill dialog — Gradient fill with color stops, style, angle and scale.

Pattern fill dialog — Pattern fill with pattern choice and scale.

To change it later, double-click the fill layer’s thumbnail or choose Layer › Layer Content › Fill Content Options…. Layer › Layer Content › Rasterize Layer turns it into a normal pixel layer.

Three fill layers stacked on top of each other — Solid color (with an elliptical mask and 60 % opacity), pattern and gradient stacked on top of each other.

A gradient you want to edit directly on the canvas is made with the Gradient tool and its Live option – see Tools.

Smart objects

A smart object wraps one or more layers together with their original resolution. You can scale, rotate and distort it as often as you like without losing quality, because everything is always calculated from the original. Filters on a smart object become smart filters, which you can change or remove later.

Command	Effect
Convert to Smart Object	Turns the active layer (or a group with its contents) into a smart object. Blend mode and opacity move to the smart object. Not possible for adjustment layers.
Edit Contents	Opens the contents in a document tab of their own (name ending in `.psb`). Edit them and save with `⌘` `S` – the smart object in the original document updates. A double-click on the thumbnail does the same.
Replace Contents…	Swaps the contents for another image file (also a PSD or a Chromatelier project). Position, transformation and smart filters are kept.
Export Contents…	Saves the contents as a Chromatelier project (`.fpd`), PSD or PNG.
Rasterize Layer	Turns the smart object into a pixel layer; smart filters are baked in.

Smart objects are also created when you bring a file into the document with File › Place Embedded….

Smart filters

If you apply a filter from the Filter menu to a smart object, its contents stay unchanged: the filter appears as a row under Smart Filters in the Layers panel.

The checkmark in front of the name switches the smart filter on and off.
A double-click on the name opens the filter dialog with the previous values (this also works for Liquify and Puppet Warp).
The × on the right deletes the smart filter.

The Lens Blur filter reads the layer mask as a depth map and therefore cannot be applied as a smart filter – rasterize the smart object first.

Smart object with Gaussian Blur and Hue/Saturation as smart filters — “Photo with smart filters”: Gaussian Blur and Hue/Saturation, each with its own checkmark.

Blurring a smart object with a smart filter

Select the layer you want to blur and choose Layer › Smart Objects › Convert to Smart Object. The smart object badge appears on the thumbnail.
Choose Filter › Blur › Gaussian Blur…, set the radius and confirm with OK.
Below the layer you now see Smart Filters and, beneath it, the Gaussian Blur.
If you no longer like the strength, double-click the filter name and change the radius. To compare, briefly remove the checkmark.
You can still scale the smart object with Edit › Free Transform (⌘ T); the filter is recalculated afterwards.

Frames

A frame is a rectangular or elliptical placeholder that you put a picture into later. Technically it is a layer with a vector mask in its shape; the picture you place becomes a smart object and fills the frame.

Frame tool (K): choose Rectangular Frame or Elliptical Frame in the options bar and drag on the canvas. This creates an empty frame layer “Frame 1”.
Layer › Frame › Convert to Frame turns a pixel layer or a smart object without a vector mask into a rectangular frame the size of its content.
Layer › Frame › Place Image in Frame… lets you choose an image file and puts it into the active frame. You can also drag a file straight from the Finder onto the frame.
Layer › Frame › Clear Frame removes the picture again.
In the Properties panel you choose Fill Frame (the picture covers the frame and is cropped on two sides) or Fit in Frame (the whole picture is visible); you also find Place Image… and Clear Frame there.

If you move or transform the frame layer, the frame and its picture move along with it.

A freshly drawn rectangular frame — A frame drawn with the Frame tool, still empty.

Layer styles

Layer styles are effects such as a drop shadow, stroke or emboss that “stick” to the shape of a layer: if you change the content, the effects follow. They do not change the pixels and can be adjusted at any time. Layers with a style carry an fx in the Layers panel.

The Layer Style dialog

You open it with Layer › Layer Style › Blending Options & Effects…, the fx button at the bottom of the Layers panel, a click on fx in a layer row, or a double-click on the thumbnail of a pixel layer. On the left are Blending Options, Fill opacity and the list of effects; on the right, the settings of the selected entry. The image shows every change immediately.

Layer Style dialog with Drop Shadow settings — The Layer Style dialog with the settings for Drop Shadow.

The box in front of an effect switches it on or off. A click on its name shows its settings and switches it on at the same time.
Fill opacity (0–100 %) fades only the layer’s pixels, not the effects. At 0 %, for example, only the stroke or the shadow of a text remains visible.
Reset effect restores the default values of the effect currently shown.
Groups and adjustment layers only have the blending options; the effects need a layer with pixels.

The effects

Effect	What it does	Settings
Bevel & Emboss	Makes the layer look three-dimensional with light and shadow along its edges (inner bevel).	Depth (1–1000 %), Direction (Up/Down), Size, Soften, Angle, Altitude (0–90°), Highlight and Shadow, each with blend mode, color and opacity
Stroke	A colored line along the edge.	Size (up to 100 px), Position (Outside/Inside/Center), blend mode and color, opacity
Inner Shadow	A shadow inside the shape, as if it were punched out.	Blend mode and color, opacity, Angle, Distance, Choke, Size
Inner Glow	A glow toward the inside.	Blend mode and color, opacity, Choke, Size, Source (Edge or Center)
Satin	Soft, silky, glossy shading inside.	Blend mode and color, opacity, Angle, Distance, Size, Invert
Color Overlay	Tints the layer with a single color.	Blend mode and color, opacity
Gradient Overlay	Lays a gradient over the layer.	Blend mode, opacity, Gradient (two colors or the color stops of a PSD file, which Two colours simplifies), Reverse, Style (Linear, Radial, Angle, Reflected, Diamond), Angle, Scale (10–150 %)
Pattern Overlay	Lays a pattern over the layer.	Blend mode, opacity, Pattern, Scale (1–1000 %)
Outer Glow	A glow around the shape.	Blend mode and color, opacity, Spread, Size
Drop Shadow	A shadow behind the layer.	Blend mode and color, opacity, Angle (−180…180°), Distance (up to 200 px), Spread, Size (up to 150 px)

Choke and Spread make the edge of the shadow or glow harder before it is blurred; Size determines how soft it becomes.

Blending options

Blend Interior Effects as Group: color, gradient and pattern overlay, satin, inner glow and inner shadow, and bevel blend with the layer’s own pixels instead of with what lies below. This matters when the layer has a blend mode other than Normal.
Knockout (None, Shallow, Deep): the layer punches a hole through the layers below it. Shallow reaches to the end of the enclosing group, Deep all the way to the background. The effect is most visible together with a low fill opacity.
Blend If: with the sliders under This Layer you hide dark or light areas of the layer; with the sliders under Underlying Layer you let dark or light areas of the layers below show through. The drop-down list chooses the channel (Gray, red, green, blue). ⌥-dragging splits a slider into two halves – which gives a soft transition.

Adding a drop shadow

Select the layer that should cast a shadow – for example a cut-out object or a text layer. The layer needs transparent areas, otherwise the shadow will not be visible.
Click fx at the bottom of the Layers panel. The Layer Style dialog opens.
Click Drop Shadow on the left; its checkbox is ticked and the settings appear on the right.
Set the Angle (which direction the light comes from), the Distance (how far the shadow is offset) and the Size (how soft it is). Opacity determines how dark it gets; the color swatch next to Multiply changes its color.
Confirm with OK. fx appears in the layer row; a click on it opens the dialog again.

Copying, pasting, clearing and rasterizing styles

The Layer › Layer Style submenu — Layer › Layer Style. Paste Layer Style only becomes active after copying.

Command	Effect
Copy Layer Style	Remembers the style of the active layer.
Paste Layer Style	Gives the active layer the remembered style (replacing its own).
Clear Layer Style	Removes all effects and blending options from the layer.
Rasterize Layer Style	Combines the layer and its effects into a pixel layer. After that, the effects can no longer be changed individually.

The Styles panel and ASL files

Window › Styles holds ready-made styles as small preview images. A click gives the active layer that style (its previous style is replaced). Styles work on pixel, text, shape, fill and smart object layers as well as on groups, but not on adjustment layers.

New Style saves the active layer’s style as a preset of your own.
Clear Style removes the active layer’s style.
Import… loads style libraries in .asl format; the styles are added to your own.
Export… saves your own styles (or, if you have none, all of them) as an .asl file.
Right-clicking one of your own styles lets you rename it or remove it with Delete Style. Built-in styles cannot be deleted.

You can also load ASL files with Edit › Presets › Load Presets….

Aligning, distributing and linking

Layer › Align aligns the selected layers with each other. If there is a selection on the canvas, even a single layer is aligned to its edge.

The Layer › Align submenu — Layer › Align with the Distribute submenu.

Align: Left Edges, Horizontal Centers, Right Edges, Top Edges, Vertical Centers, Bottom Edges. These need two or more layers, or one layer and a selection.
Distribute: the same six reference lines plus Horizontal Spacing and Vertical Spacing (equal gaps between the layers). These need three or more layers.

The same commands are available as icons in the options bar of the Move tool (V).

Layer › Link Layers links the selected layers: when you move one of them, the others move along. Linked layers carry a chain icon. If the active layer is linked, the command is called Unlink Layers.

Merging and the background layer

Command	Shortcut	Effect
Layer › Merge Down	`⌘` `E`	Merges the active layer with the pixel layer directly below it (in the same group). The lower layer must not be hidden or locked. Effects are baked in. If a group is active, the command is called Merge Group; with several layers selected, Merge Layers.
Layer › Merge Visible	`⌘` `⇧` `E`	Combines all visible layers into one layer “Merged”. Hidden layers are kept.
Image › Flatten Image		Combines all layers into a single layer “Background”. Transparent areas turn white.

Merged layers can only be separated again with Edit › Undo or the history. Save a version with layers first if you may want to change something later.

Artboards

Artboards are several work areas in one document – for example the same design for smartphone, tablet and desktop. Each artboard is a group with its own size; its name appears above it on the canvas.

Choose Layer › New › New Artboard…. If there is a selection, the dialog suggests its size; otherwise the size of the canvas.
Enter a Name and choose a preset under Size (such as Web 1920 × 1080, iPhone 15, Instagram post 1080 × 1350, Square or A4 at 150 ppi), or enter the Width and Height yourself.
Set a color under Background, or remove the checkmark for a transparent background.
Confirm with OK. The new artboard is placed to the right of the existing ones; the canvas grows to fit.

File › Export › Artboards to Files… saves each artboard as a file of its own (see Saving, Export & Printing).

Layer comps

A layer comp remembers a state of the Layers panel so you can switch quickly between variants – for example one version with text and one without. You open the panel with Window › Layer Comps.

New Layer Comp saves the current state as “Layer Comp N”.
A click on an entry restores that state; ◀ and ▶ step through all comps.
Right-clicking an entry opens its settings: the name, and what the comp remembers – Visibility, Position and Appearance (Layer Style). There you also find Update Layer Comp (takes over the current state) and Delete Layer Comp.

Comps are saved with the document. Layers whose content would leave the canvas when a comp is applied are not moved; the status bar tells you about it. File › Export › Layer Comps to Files… saves each comp as an image of its own.

Video layers

Layer › New › New Video Layer from File… brings a video clip (MP4, M4V or MOV) into your document as a layer. The layer shows the frame at the current position of the timeline and, like other layers, can be masked, corrected with adjustment layers and blended. Rasterize Layer turns it into a pixel layer with the frame currently shown. Everything else – timeline, keyframes, sound and export – is described in the chapter Video & Animation.