Preparing AIA data

The common usecase for aiapy is to transform level 1 AIA data to level 1.5. This is called aia_prep.pro procedure in SSWIDL as described in the SDO Analysis Guide.

The following example, Registering and aligning level 1 data showcases how to mimic this in Python via aiapy.

If you want to do more advanced things, for example, a PSF deconvolution. You will want to do it in the following order:

1. PSF deconvolution (aiapy.psf.deconvolve)

2. Pointing correction (aiapy.calibrate.update_pointing)

3. Registration (aiapy.calibrate.register)

4. Degradation correction (aiapy.calibrate.correct_degradation)

5. Exposure normalization (aiapy.calibrate.normalize_exposure)

A few notes on this:

• The PSF functions are defined on the level 1 pixel grid so PSF deconvolution MUST be done on the level 1 data products (i.e. before image registration). This is described in the PSF gallery example Deconvolving images with the instrument Point Spread Function (PSF).

• The pointing update should be done prior to image registration as the updated keywords, namely CRPIX1 and CRPIX2, are used in the image registration step. More details can be found in this gallery example Updating pointing and observer keywords in the FITS header.

• The exposure time normalization (aiapy.calibrate.normalize_exposure) and degradation correction (aiapy.calibrate.correct_degradation) operations are just scalar multiplication and are thus linear such that their ordering is inconsequential.

• Level 1.5, in its typical usage, only includes steps 2 and 3. Unless stated otherwise, a science publication mentioning level 1.5 AIA data does not include steps 1, 4 and 5.