# piSOFIT
*processing-chain . standards*

Atmospheric correction processing chain used by Pixxel for Firefly hyperspectral imagery. Pixxel implementation of the NASA JPL ISOFIT optimal-estimation framework, with a neural-network MODTRAN radiative-transfer emulator, superpixel aerosol and water-vapour retrieval, and per-pixel Bayesian uncertainty propagation. Produces Level-2A surface reflectance with uncertainty layers from upstream Level-1 radiance.

## Specifications
- **version**: operator-managed, no public version tag
- **authority**: pixxel
- **url**: https://support.pixxel.space/hc/en-us/articles/20497730652700-Atmospheric-Correction-ISOFIT-model
- **last verified date**: "2026-05-19T00:00:00.000Z"
- **verified by**: sw
- **claim status**: unclaimed

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Source: https://eo-atlas.org/standards/pisofit
Maintainer: SpectraWorks B.V. (CC-BY 4.0)