What to try
- Click the source image or use its arrow keys to choose a pixel; follow its tone onto the ramp.
- Choose Coastal light or another Print palette, then move the middle stop or reverse the tone direction.
What to look for: The selected location stays fixed while its tone chooses a new color. Similar encoded tones use similar ramp positions wherever they occur in the image.
How it works
The Lab computes a luminance-like value from encoded RGB channels and treats it as a position along the gradient. Dark pixels sample the beginning, light pixels the end, and intermediate values interpolate between surrounding stops. Stop placement controls how much of the tonal range receives each color.
This differs from laying a spatial gradient over the canvas. A gradient map follows the image’s values wherever they occur. Reversing the stops exchanges the tonal roles of colors; the Amount setting blends the mapping with the existing image.
Use it in the Lab
Use a gradient map after a noise field, edge treatment or grayscale study to build a controlled palette. Compare sRGB, Lab and OKLCH interpolation and record the stops in a reusable chain.
Limits & distinctions
Gradient mapping is not indexed-color quantization. Interpolated samples can create many intermediate colors between the stops.
Sources & references
Guide updated