# 📐 L2 Spec — Ptychography Mismatch-Only Spec
**ID:** `L2-070-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-070`](/artifact/l1/L1-070)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.58 · **Delta tier:** 5
> **⛓ On-chain block:** 41554172
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 128 – 4096 |
| W | px | 128 – 4096 |
| J scan | — | 50 – 10000 |
| Probe size | — | 32 – 512 |
| Photon count | — | 10 – 100000 |
| Overlap fraction | — | 0.3 – 0.85 |
| Partial coherence | — | 0.7 – 1.0 |
| Probe shape drift | — | 0.0 – 0.2 |
| Background scatter | — | 0.0 – 0.1 |
| Probe position error | — | 0.0 – 2.0 |
## 2. Tolerance (ε)
**Type:** `fn`
```
24.0 + 3.0 * log2(J_scan / 50) + 2.0 * log10(photon_count / 10) - 15.0 * max(0, 0.5 - overlap_fraction)
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.58 |
| Delta tier | 5 |
## 4. Fingerprint
`96f5058a7c3afd52966bf6f56cf79a89d7d922f6072946cf7c36932ed883ec9c`
## 5. On-chain Registration
- **Chain hash:** `0xb252b961733ebe2a667ea9532fc57ac267dc842326c8709f89ee326d640531dc`
- **Chain tx hash:** `0x3055ab5abb7bc520af951dddd4f3321e050dfb797b6a7383f8ecb97bb7598958`
- **Chain block:** `41554172`
---
## File Mapping
This bundle consists of: `L2-070-001.md`, `L2-070-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-070-001.md` | Source of truth — edit this | Human or LLM |
| `L2-070-001.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 `L2-070-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._