# Investigation Context (Scale, Distortion & Documentation)

## Module Overview

A reconstruction is only as strong as its documentation. This module is about turning a 3D model into something that can be **scrutinized and defended**: being honest about scale limits, accounting for distortion, quantifying uncertainty, and recording the methodology so another investigator could reproduce it. This is what separates a reconstruction that holds up from one that collapses under questioning.

## Scale Limits

[TODO: no reconstruction is infinitely precise. The accuracy of your scale is bounded by your best scale reference (the scale pillar from Module 04) and your imagery resolution. How to state a scale limit honestly — e.g. "dimensions accurate to within ±5 cm given the door-frame reference," not "exactly 2.4 m."]

## Distortion

[TODO: the sources of distortion that can silently move your model — lens distortion (barrel/pincushion) in the matched photo, satellite imagery projection error, and the assumption of a perfect pinhole camera. Why undistorting the source image before matching matters, and how residual distortion shows up as drift at the corners of a photomatch.]

## Uncertainty & Honest Presentation

[TODO: how to present uncertainty rather than hide it — error bars / ranges on key measurements, clearly labeling what is *measured* vs. *assumed* vs. *estimated*, and the difference between a reconstruction that is "right" and one that is "right within stated limits." Reference the [Validate & Report](../../foundation/03-data-and-methodology/validate-report.md) page.]

## Documentation Requirements

[TODO: the minimum defensible record. Capture conditions, source imagery provenance, reconstruction software and versions, camera-solve parameters, scale reference and its source level, cleanup decisions, and the date performed. Frame it against the [Berkeley Protocol on Documentation of Conflicts](https://www.berkeleyprotocol.org/) standard where relevant.]

## Knowledge Check

[TODO: 3 questions — e.g. what a scale limit is; why lens distortion must be corrected before matching; what the minimum documentation record should contain.]

## Summary

[TODO: one paragraph.]

## KB References

- [Validate & Report](../../foundation/03-data-and-methodology/validate-report.md) — the validation workflow
- [Measurements, Scale & Dimension](../../../techniques/1-foundation-preparation/measurements.md) — scale hierarchy and limits
- [Scale Estimation](../../../techniques/1-foundation-preparation/scale-estimation.md) — the scale pillar in full