CharacterizeImageTask.detectMeasureAndEstimatePsf() is called in a for loop, and calls self.measurement.run(). This means that every enabled measurement plugin is run during PSF iteration. Even with cleaned up plugin list in DM-35060, we are still likely doing more calculations than necessary in this loop: the final measurement values of interest come out in the self.measurement.run()-call in CharacterizeImageTask.run() after the final PSF has been determined. This may require setting up a separate SingleFrameMeasurementTask to do the measurements in the PSF loop, and whether we want that to be a configurable option.

MeasurePsfTask uses ObjectSizeStarSelector, which makes use of flags, GaussianFluxes, centroids, and shape moments, so I believe the only plugins we need here are the following:

• base_PixelFlags
• base_SdssCentroid
• base_ext_shapeHSM_HsmSourceMoment
• base_GaussianFlux

This ticket is part of the implementation of RFC-857.