# 📐  L2 Spec — Photogrammetry Structure-from-Motion — Nominal + Mismatch Specs

**ID:** `L2-470-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-470`](/artifact/l1/L1-470)

> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.3 · **Delta tier:** 5
> **⛓ On-chain block:** 41555302

---

## 1. Domain Ω

**Type:** `range`

| Parameter | Unit | Range |
|---|---|---|
| N gcps | — | 0 – 50 |
| N images | — | 10 – 10000 |
| Overlap percent | — | 50 – 95 |
| Flight altitude m | m | 30 – 2000 |

## 2. Tolerance (ε)

**Type:** `fn`

```
2.0 + 1.0 * (flight_altitude_m / 120) ** 0.5
```

## 3. Difficulty

| Property | Value |
|---|---|
| Difficulty score | 0.3 |
| Delta tier | 5 |

## 4. Fingerprint

`b47d6720835d423c12da64cf3bd426fd3b6f8cf10e57420e8b79862763f7c0ce`

## 5. On-chain Registration

- **Chain hash:** `0x1721dc4c4984a6e4244f6cd54ccdec46c8f137578e2d610a827d752be0f6e733`
- **Chain tx hash:** `0x04f90357aad4404c088cbc242415d9174ebd73220ff8270d9839472e0578a4bb`
- **Chain block:** `41555302`

---

## File Mapping

This bundle consists of: `L2-470-001.md`, `L2-470-001.json`.

| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-470-001.md` | Source of truth — edit this | Human or LLM |
| `L2-470-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |

**Prompt for your LLM after editing this Markdown:**

> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.

_This Markdown was auto-synthesized from the catalog row for `L2-470-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._