Blend Modes

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Effects in a composition lie on top of each other in layers. A Blend mode is the rule by which the next effect combines with the picture already assembled from the effects beneath it: simply cover it, add up brightness, multiply colors, or cut it out by a stencil. Together with opacity, this is the main tool used to build a complex animation out of several simple effects.

The mode is set for each effect individually and works the same way everywhere: in the preview on the Mapping field, in the 3D View, in the Art-Net signal, and in the exported cue file.

Where to set the mode

The blend mode is chosen from a drop-down list, available in two places:

  • in the Timeline window — on the left side, in the effect's row, next to its name;
  • in the Properties window — select the effect, the list is at the very top, to the right of the effect's name. Right-clicking this list immediately resets the mode to Normal.

The list is available for all effects that draw an image. Effects that control fixture channels directly (for example Set Channels), and audio tracks, have no blend mode — they don't draw anything on the field.

The selected mode is saved in the project and carries over with the copy of the effect when it is duplicated.

Layer order

Blending always goes from bottom to top, so the result depends on the order in which the effects are arranged on the timeline.

  • The program stacks all effects of the composition that are playing at a given moment into a single stack in the same order they are listed on the left side of the Timeline: the bottom row is the bottom-most layer, the top row is the top-most.
  • The stack is shared across the whole composition: effects from different layouts fall into it together. An effect from a layout positioned higher on the timeline lies on top of the effects of the lower layouts — wherever the layouts overlap on the Mapping field. If the layouts don't overlap, the effects work on different fixtures and don't blend at all.
  • Each layer blends not with a single neighbor, but with the entire picture assembled from all the layers beneath it.
  • The stack starts with an empty transparent frame. The bottom-most effect has nothing to blend with: regular modes behave there as Normal, while darkening and masking modes produce a black screen. The bottom layer is almost always left at Normal.

The order is changed by dragging the effect's row on the left side of the timeline — up or down within a layout, see Moving Effects Between Layouts. Only the order among effects playing at the same time matters: if the effect bars don't overlap in time, there's nothing to blend.

Opacity

The first parameter of any effect is Opacity, a value from 0 to 255, 255 by default. It works together with the blend mode and sets how strongly the top layer affects the picture: at 255 the mode acts at full strength, at 0 the effect is not visible at all, intermediate values blend the result with what was beneath it.

Opacity is animated with keyframes — this is how appearances, fade-outs, and smooth transitions between effects are made (see Ключевые кадры и параметры эффектов).

Don't confuse it with the overall brightness slider on the Timeline panel (enabled by right-clicking the playback buttons): it dims the already-assembled picture as a whole and doesn't affect the blending of layers.

List of modes

The names below are given as they appear in the interface.

Normal

Mode What it does
Normal The top effect simply covers what's beneath it, wherever it is opaque. The default mode

Lightening

The picture becomes lighter, fixtures glow brighter. This is the most familiar group for lighting: light adds up instead of blocking.

Mode What it does
Linear dodge Simple addition of brightness — like two spotlights shining on the same point. The most predictable way to show two effects at once; quickly blows out to white in bright areas
Screen Soft addition: black areas of the top effect change nothing, light areas brighten the picture. Unlike simple addition, doesn't produce harsh overexposure
Lighten At each point, the lighter of the two layers is taken. The top effect is visible only where it's brighter than the layer below
Color dodge Sharply brightens the layer below wherever the top layer is light. Produces harsh flashes and blown-out highlights

Darkening

The picture becomes darker — these modes are used to dim and tint what lies below.

Mode What it does
Multiply Colors are multiplied: white in the top effect changes nothing, black darkens, colored tints. Convenient for tinting or dimming the animation below. Where there's nothing beneath it, nothing appears
Linear burn Darkens more strongly than Multiply: brightness values are subtracted, dark areas quickly go to zero
Color burn Darkens the layer below and also increases its contrast — midtones disappear, shadows become deeper

Contrast

These modes both brighten and darken at the same time, depending on the brightness of the layers. Good for "livening up" a flat fill or getting sharp graphics.

Mode What it does
Overlay Multiplies the dark areas of the layer below, brightens the light ones: contrast and saturation increase, overall brightness is preserved
Vivid light The same, but harsher: light areas of the top effect strongly brighten the picture, dark ones strongly darken it
Linear light An even sharper version of the same thing: brightness is added and subtracted linearly, almost no midtones remain
Hard mix Reduces colors to the extreme values of the channels: the result is a few pure colors with no gradients, a "poster" look
Difference The difference between colors is taken: identical colors give black, opposite ones give bright. Produces unexpected inversions where effects intersect

Masks

In these modes the effect doesn't draw itself, but serves as a stencil for everything beneath it — in all layouts at once.

Mode What it does
Alpha mask The layers below are visible only where this effect has an image; elsewhere the fixtures go dark
Alpha mask inv The opposite: where the effect has an image, the layers below go dark, while the surrounding area stays visible
Luma mask The effect's brightness serves as the stencil: where it's light, the layers below are fully visible, where it's dark, they go dark. The transition is smooth, through midtones
Luma mask inv The opposite: the layers below are visible where the mask effect is dark

It's convenient to make a masking effect out of simple effects with a clear shape — text, a rectangle, an ellipse, a gradient, an image with a transparent background.

Common techniques

Show two effects at once. Set the top one to Linear dodge or Screen — instead of covering the one below, it will add to it. If the picture becomes overexposed, lower the top effect's Opacity.

Tint or dim an animation. Place a solid-fill or gradient effect on top of it and set it to Multiply: the animation below will take on that color, while its dark areas stay dark.

Limit an animation to a shape. Place an effect with the desired shape — text, a figure, an image — on top and set it to Alpha mask: the effects below will only glow inside that shape. To cut a shape out of the animation instead, use Alpha mask inv.

Smooth transition between effects. Lay out the effect bars overlapping in time, leave the top one at Normal, and in the overlap zone animate Opacity from 0 to 255 with keyframes. See Расстановка эффектов по времени.

Reveal wave. Place an effect with a smooth gradient or noise on top of the finished animation and set it to Luma mask: the picture below will appear and fade following the movement of the gradient.

If the result isn't what you expected

  • Nothing changed. The effect is most likely already the bottom-most one — there's nothing for it to blend with. Check that something is actually playing beneath it at this point in time: the effect bars must overlap in time.
  • The screen went black. A darkening or masking mode is set on the bottom effect, or there's nothing beneath it. Set it back to Normal, and set the blend mode on the effect that lies above it instead.
  • The top effect covers everything. Many effects fill their entire layout opaquely — with the Normal mode, nothing is visible beneath such a layer. Switch the mode to a lightening one or lower the Opacity.
  • The effects don't blend even though they're next to each other. Check the layouts: if they don't overlap on the Mapping field, the effects work on different fixtures. See Creating and Editing Layouts.
  • The effect isn't visible at all. The checkbox next to its name is unchecked, opacity is set to zero, or the effect bar doesn't fall under the time cursor.
  • The layout properties also have a Blend mode field, but the blending of layers within the composition is controlled by the modes set on the effects themselves.

See also