Page History

Overview

This page attempts to capture at a high level the software and algorithm development necessary to implement both Level 2 Calibrated Exposure Processing, though it also covers most of the code that will be used in Level 1 Calibrated Exposure Processing; the Level 1 processing should be mostly a subset of the Level 2 processing, with some slight reordering of operations and an emphasis on speed rather than precision.  As of this writing, this page is mostly focused on the gap between our code's current capabilities and the capabilities needed at first light, while the linked pages above are more concerned with fleshing out the algorithms in detail.  The long term relationship between these pages is TBD.

The rough outline for the Level 2 processing is:

1. Run ISR on each snap exposure (sensors or even amplifiers in parallel).
2. Coadd two snap exposures into a single visit exposure (sensors in parallel).
3. Iterate:
   1. Model Background (sensors in parallel, at least at first).
   2. Detect (possibly Deblend) and Measure bright sources (sensors in parallel).
   3. Run Astrometric/Photometric Calibration (sensors in parallel, at least at first).
   4. Estimate PSF (all sensors together, at least during one iteration).
4. Determine Aperture Corrections
5. Detect, Deblend, and Measure faint sources (sensors in parallel)
6. Apply Aperture Corrections to both bright and faint sources

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