You render a portrait on a Krea 2 fine-tune and it looks great — until you zoom in. The skin is peppered with tiny dark and bright dots, or the background is covered in coloured confetti. It is tempting to treat it as one problem. It is two, stacked, and each has its own fix.
Rule zero: judge at 4× crops
Both artifacts vanish when you look at a downscaled preview or a contact strip, so you will “fix” them by accident and break them again. Crop a 256-pixel patch of cheek and a patch of background and view them at 400%. Compare settings only that way.
Artifact 1: confetti from the sampler chain
Coloured, high-frequency specks, worst in flat areas like walls and sky. These come from sampler extensions that inject noise or extra guidance between steps — the “refine” style node chains popular on Civitai. On Krea 2 they overshoot.
The fix is boring on purpose: a plain KSampler.
sampler res_2s scheduler beta steps 20 cfg 1.0
Artifact 2: skin speckle from fp8 weights
Fine dark-and-light grain only on skin, still there with a plain sampler. This one is in the checkpoint: some fine-tunes were published as fp8, and the rounding shows up exactly in smooth skin tones. The same model saved as int8 (or bf16) does not do it.
If a checkpoint offers an int8 build, use it. If it doesn’t, try the official Krea 2 RAW with the turbo LoRA at 0.6 — slightly less stylised, but clean.
Checklist
- Plain KSampler, res_2s / beta, 20 steps.
- int8 or bf16 weights, never fp8, for skin-heavy work.
- Judge at 4× crops of skin and background, not on the full frame.
- At CFG 1 the negative prompt does nothing — put exclusions like “no logos” in the positive.
Both fixes are already baked into the free Krea 2 and IntoRealism workflows. The rest of this course comes with Pro.