The organising rule
The blend mode list is divided into groups, and each group has one behaviour:
- Darken group (Multiply, Colour Burn) — result is never lighter than the original. White becomes invisible.
- Lighten group (Screen, Colour Dodge) — result is never darker. Black becomes invisible.
- Contrast group (Overlay, Soft Light, Hard Light) — lightens the light parts and darkens the dark parts. 50% grey becomes invisible.
- Comparative (Difference, Exclusion) — mostly used for alignment, not aesthetics.
- Component (Hue, Colour, Luminosity) — takes one attribute from this layer and the rest from below.
Knowing which colour disappears in each group is what lets you predict the result instead of scrolling the list.
The six you will actually use
- Multiply — darkens. Puts shadows onto a surface and drops white backgrounds out of scanned line art.
- Screen — lightens. Adds glows, flares, smoke and fireworks from a black background.
- Overlay / Soft Light — adds contrast. Soft Light is the gentler of the two and the basis of dodge and burn.
- Colour — takes hue and saturation from this layer, brightness from below. This is how you recolour an object without flattening its texture.
- Luminosity — the reverse. Put a sharpening or contrast layer in Luminosity to stop it shifting colours.
Two practical tricks
Cycle modes with Shift + and Shift − to audition them quickly rather than reading the menu.
And use Luminosity on your contrast layers as a default. A strong S-curve in Normal mode increases saturation as a side effect, often past the point where skin tones stay believable. Switching that layer to Luminosity keeps the contrast and leaves the colour alone.