Dark halo in gray colors, (Color shift from the VAE sRGB > Linear)
I’ve been wrestling with a strange “dark halo” showing up around masked regions whenever I run a k-sampler / Flux-Redux fill pass in ComfyUI. It only appears on gray flat backgrounds around masks you can see a subtle darker band even though the underlying flat gray should be uniform (see attached image).
What I’ve already tried:
sRGB→Linear→k-Sampler→Linear→sRGB sandwich around the sampler to do the interpolation in true linear light.
Edge padding (clamp-to-edge) via the ImagePad KJ node, then cropping back down to avoid sampling black borders.
Swapping VAEs flux_ae.safetensors, the community clip+vae bundle, fp8/distilled, NF4-quantized nothing changed.
Post-fill color match / color grade on the filled region to re-tone back to the 50% gray background.
Despite all that, I still get the same faint dark shift. I’m pretty sure it’s the gamma bias from sampling in sRGB combined with the mask boundary, but I can’t nail it down.
