reference-look-calibration git:20260921.d4bf893A

Immutable. This exact content is served forever at /api/v1/blob/a4f026551a547761.

---
name: reference-look-calibration
description: Calibrate Blender materials, lighting, camera crop, emission/glow, color management, and aura/HUD styling against supplied original/reference images using measurable color, brightness, saturation, bbox, and mask statistics. Use when a product must match the lighting/look of a source image or when audits say the product is too bright, desaturated, wrong hue, wrong glow, or wrong silhouette extent.
when_to_use: Reference-based look-dev, lighting/material/color calibration, original-image visual matching, glow/aura/HUD matching, HSV/brightness/mask fit reports, final look pass after geometry and UV are locked.
allowed-tools: Read Bash Glob Grep mcp__blender__execute_blender_code mcp__blender__get_scene_info mcp__blender__get_object_info
---

# Reference Look Calibration

This skill handles the final visual match after geometry and UVs are locked. It must not compensate for wrong shape, wrong UVs, or wrong camera framing.

## Inputs

- accepted geometry / UV fit reports;
- reference/original image(s);
- product preview render(s);
- optional mask overlays and multiview fit reports.

## Metrics

Use `scripts/look_fit_report.py` to compare:

- object/bright-mask IoU and bbox extent;
- configured hue-band mask IoU for glow/accent assets;
- mean/std HSV and BGR under object mask;
- brightness p95 / mean;
- saturation mean;
- hue drift.

## Calibration order

1. Camera crop / orthographic scale — object extent must match before color tuning.
2. World/background darkness.
3. Base material hue/value/saturation.
4. Emission strength and glow color.
5. Aura/HUD ring color and thickness.
6. Color management / exposure / gamma.
7. Final render overlay and metrics.

## Hard rules

- Do not tune lighting before geometry/UV fit gates pass.
- Do not change accent/glow hue away from the source reference unless the user explicitly asks.
- Do not hide mismatched geometry with bloom, fog, or overexposure.
- Write look metrics before and after calibration.

## Handoff

Consumes `validation/multiview_fit_report*.json` and product previews. Produces `validation/look_fit_report.json`, look overlays, and updated material/light/render settings.