Color Blend

If you've used Photoshop or GIMP, this is the "Color" blend mode as a ComfyUI node. It takes the brightness and detail from one layer and the hue and saturation from another, and merges them: one image supplies the shape of the image (its luminance - the light and dark structure that makes it recognizable), the other supplies the color. The classic use is colorizing a black-and-white image using a color reference, but it's just as useful any time you've got a sharp grayscale/luma pass and a separate color pass you want recombined without losing either.

How it works

bw_layer provides luminance; color_layer provides hue and saturation. The node combines them the way the Color blend mode always has - the output keeps the tonal structure (highlights, shadows, edge detail) of bw_layer while taking its actual color from color_layer. It's not a crossfade between the two images; it's a genuine separation of "how bright" from "what color," recombined from two different sources.

The inputs and outputs that matter

Two required inputs, both IMAGE:

• bw_layer - supplies the luminance/detail. Doesn't have to be literally grayscale - only its brightness information gets used, so a full-color sharp image works here too if you're layering color from elsewhere.
• color_layer - supplies the color. This is what determines the final hue and saturation.

One output: IMAGE, the recombined result.

How to install it

Part of the Art Venture pack. ComfyUI Manager: search comfyui-art-venture, install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/sipherxyz/comfyui-art-venture

Restart ComfyUI. No model downloads - this is a pure image-math node.

Common issues & troubleshooting

Result looks washed out or barely colored. color_layer is probably low-saturation to begin with - the node can only pull color that's actually present in that layer. Boost saturation on color_layer upstream (a color-correct node, or regenerate it with more vivid tones) before blending.

Output looks nothing like either input. That's actually correct behavior for this blend mode when the two sources disagree wildly - if bw_layer and color_layer are unrelated images rather than two versions of the same composition, you'll get a strange mismatch of one image's shapes wearing another's colors. This node works best when both inputs are the same underlying image (or closely aligned), just processed two different ways.

Mismatched resolutions error out or look wrong. Both images should be the same size before they hit this node - resize one to match the other first if they came from different sources or generation passes.

Wanted a simple crossfade, not this. Wrong node - a Color blend always keeps the darks and lights of bw_layer, no matter what color_layer looks like; it never just averages the two images together. If you actually want to layer one image over another using transparency, that's ImageAlphaComposite instead - a different operation, worth not confusing with this one.