comfyui-workflows/optimized/notes/flux2klein.md

FLUX.2-klein Notes

Current default assumptions

• Chris uses FLUX.2-klein 9B.
• Prefer 9B fp8 paths first.
• GGUF is not the default path unless it is the only strong or practical workflow route.

Strong current source workflows

• Official Comfy image edit templates:
  • image-edit-9b-base
  • image-edit-9b-distilled
  • image-edit-4b-base
  • image-edit-4b-distilled
• The maintained flux2klein-9b-fp8-edit-master now lines up with the real 9B fp8 diffusion filename and full_encoder_small_decoder VAE, so the documented model pair matches the saved graph instead of the older mixed-label shorthand.
• Current best outpainting starter:
  • models/flux2klein/image-edit-4b-distilled/
  • Reason: official, current, and easiest first test even though Chris's main stack is 9B
• Community Hugging Face workflow worth remembering:
  • models/flux2klein/community-gguf-kv-yarvixpa/
  • Interesting because of KV-cache / GGUF optimization ideas, not because it is the default path
• Community multi-reference donor worth watching:
  • models/flux2klein/geceff-flux2klein9b-multiref-3image/
  • Useful as a reference-control donor, but still too heavy and opinionated to replace the official 9B fp8 edit baseline by default

Strong current heuristics

• Prefer official Comfy templates as the baseline unless a community workflow clearly improves something real.
• For 9B, watch closely for text-encoder mismatches.
• Community 9B optimization notes often revolve around:
  • low-step usage
  • CFG=1
  • cleaner model/text-encoder pairing
  • avoiding broken loader substitutions
• Keep the official 9B fp8 edit master as the default lane, then borrow from the multi-reference donor only when reference control is the real problem.

Current weak areas

• We still do not have a clean, trusted, explicitly labeled 9B fp8 outpainting community workflow import.
• Some public workflow pages mention outpainting but do not expose a trustworthy raw workflow asset.
• The multi-reference donor is promising, but it is not a clean maintainable replacement for the current edit master.

Best current optimization direction

• Build future optimized/image-edit/flux2klein-9b-master/ from the official 9B edit template family first.
• Borrow only proven improvements from community sources:
  • cleaner graph organization
  • low-step settings when they are clearly validated
  • better reference/outpaint control if portable
• Treat the geceff multi-reference pack as a donor for future reference-heavy variants, not as the first default promotion.
• The 2026-08-22 overnight image-edit-9b-distilled smoke stayed clean enough to keep the current flux2klein-9b-fp8-edit-master lane as the benchmark winner for now: strong identity retention, a tidy full-body silhouette, and a clean white background. Keep one more smoke test queued before any broader claim of stability.
• The 2026-08-23 overnight image-edit-9b-distilled smoke is still clean enough to keep flux2klein-9b-fp8-edit-master as the benchmark winner: identity stayed locked, the body read stayed clean, and the white background remained uncluttered. Queue another smoke test before any stronger promotion.

What needs Monday proof

• Whether 9B distilled or 9B base is the better real default for edit/outpaint on Chris's setup
• Whether a 4B distilled outpaint starter still beats 9B in practical iteration speed enough to matter
• Which custom-node optimizations are real versus noise