Current only sources have parameters. But sometimes we have to adjust the mapping between the observational frames and the model frame, e.g. when the astrometry is off.
The way to do that is to allow Observation to declare parameters, and to pass them from Blend as Observation.get_loss(model, *parameters).
Specifically, an astrometric offset could be corrected by using a Fourier-space shift (same thing we do in ImageMorphology) when we do the convolution. Another possible but more delicate parameter would be the PSF model itself.
This PR is only to create the framework to create and pass observation parameters.
Current only sources have parameters. But sometimes we have to adjust the mapping between the observational frames and the model frame, e.g. when the astrometry is off.
The way to do that is to allow
Observationto declare parameters, and to pass them fromBlendasObservation.get_loss(model, *parameters).Specifically, an astrometric offset could be corrected by using a Fourier-space shift (same thing we do in
ImageMorphology) when we do the convolution. Another possible but more delicate parameter would be the PSF model itself.This PR is only to create the framework to create and pass observation parameters.