Eric Krea2 Sweep Plan

Every fine-tune has a preferred sampler, scheduler, step count and mu - and all of them are really proxies for one thing: how far that model's training eroded the turbo distillation. Instead of guessing, this node measures. Wire Eric Krea2 Sweep Plan into Ultra V2's sweep input (the last socket), fill in the axes you want to test, and one queue item runs the whole grid against a fixed seed: per-cell PNGs with the full recipe embedded, a labeled contact sheet, sweep_summary.csv, and a JSON manifest. It turns sampler folklore into a spreadsheet.

Grid mode vs combos mode

There are two ways to tell it what to run, and mode picks between them.

Grid is the default: fill any axis field and the node takes the cross product. The ones you'll actually set first:

• samplers - all 13 ship pre-populated (euler, res_2m, res_2s, deis_3m, abnorsett_3m/4m, lawson4_4s, etdrk4_4s, er_sde, rk6_7s, lcm, the hybrids). Delete what you don't want; blank = not swept.
• schedulers - built-in curves and saved ★ sigma-preset names mixed freely; each entry resolves as a schedule first, then as a sigmas preset. Unknown names are skipped with a console warning, never an abort.
• steps, windows (e.g. 5-12, 6-12 → start/end step), etas, noise_types, cfgs, shift_modes/mus, hybrid_steps, megapixels.

pair_lock zips samplers+schedulers into fixed pairs for testing a known recipe; off = full cross product. max_combos (default 64) is a hard cap - over-cap plans refuse with an axis-size breakdown rather than silently truncating, which is the honest behavior you want.

Combos mode skips the grid: one JSON object per line in combos_json (or a file via combos_file), using the same widget keys as Ultra presets and PNG recipes. {"s2_sampler": "lcm_hybrid", "s2_steps": 12, "s2_start_step": 6} - copy-pasteable straight off a stamped image. Campaigns become versionable files.

The knobs that shape a sane sweep

stage_scope (s1 / s2 / s3 / all_stages) decides which stage the swept keys hit, and the workflow intent is spelled out in the tooltip: perfect Stage 1 first, then sweep s2/s3 refinement on the short list. quick_screen forces S1-only at screen_megapixels for cheap wide grids - and for s2/s3-only sweeps, the post-S1 latent is computed once and reused across cells, which is what makes a 40-cell refine sweep finish in minutes.

The newer axes are where this gets genuinely interesting for Krea 2's ecosystem: lora_mode=bakeoff tests each style LoRA against the bare checkpoint (the lora_triggers field even merges each LoRA's trigger words into its cell's prompt), prompts adds a prompt axis (slowest, deliberately), and sigma_profiles sweeps saved sigma shapes as full per-cell profiles. Failed cells never kill a sweep - red tile plus a manifest error - and interrupts finalize the files on disk before the queue stops.

Wiring and install

enabled (default on) means "off = the node outputs nothing and Ultra runs a normal single generation" - you can leave the sweep wired in and toggle it. sweep_preset backs onto sweep_presets.json; selecting one writes its values into the panel so you always see exactly what will run, and editing any field flips it back to custom.

It ships with the rest of the pack:

cd ComfyUI/custom_nodes
git clone https://github.com/EricRollei/Krea2_ComfyUI_Advanced

Restart, and remember the pack needs a diffusers build with Krea2Pipeline plus Krea 2 weights - see the pack README for the --force-reinstall install from the HF git repo.

Where people get burned

Watch out for axes that differ only by inert knobs - the plan dedupes cells where eta/noise don't apply (e.g. on euler/lcm), but it can't read your mind about whether sweeping megapixels is worth the VRAM. Resolution changes the noise grid, so composition shifts with size even at a fixed seed; that's part of what you're measuring, but it makes megapixels sweeps noisier to read. Start wide with quick_screen, narrow with stage_scope, and let Sweep → Preset promote the winners.