Tutorials

These tutorials are runnable Jupyter notebooks from the notebooks/ directory of the repository, rendered here with their saved outputs. Each one is self-contained. Download it and run it interactively to experiment. The Gaia queries they perform are cached in notebooks/gaia_cache/, so they run offline.

Start with the first two: notebook 01 simulates a field and shows the standard views in a few minutes, and notebook 02 checks that the images behave like data. The rest each cover one topic.

Notebook	What it covers
Getting started with wcc-sim	Simulate a full frame, overlay the Gaia catalog, compare the three PSF modes on one star, and write the FITS file.
Verifying the simulated images	The checks: PSF peak ordering, astrometric residuals, photometric closure on the ETC rates, noise statistics, saturation flags, and the FITS round trip. Every section ends in an assertion.
PSF focus modes: Airy vs defocus	The three PSF modes (in-focus Airy, +1/+2-wave defocus), stamp sizes, oversampling, and the effect of jitter.
Detectors, filters, and count rates	The two detectors (IMX455 vs qCMOS), sensorfilter keys, and how Gaia photometry maps to spectral types and count rates.
Noise and saturation	The ETC noise model step by step, `n_reads` semantics, per-pixel saturation masks, and the windowed per-star `saturated` flag.
Astrometry, WCS, and custom catalogs	The TAN WCS, position angles, injecting your own catalog, and astrometric round-trip checks.
The command line and the FITS output	The `wcc-sim` command line and the multi-extension FITS output, read back with astropy.
PSF wings: no more postage stamps	The analytic PSF wing extension: before/after images at hard stretch, the fitted power-law wing models, seam smoothness at the old stamp edge, and how the wings change the encircled energy.
wcc-phot: differential photometry of a WCC image series	The `wcc_phot` differential photometry pipeline: target + reference selection, per-frame centroiding, aperture vs PSF fluxes, the relative light curve, and the live viewer hook.
Plotting: every .plot_* method in one place	Every `.plot_*` method once: images with catalog and saturation overlays, cutouts, the PSF radial profile, stamps and encircled energy, and the photometry panels, all with `ax=`.