Ticket #1552 (closed enhancement: fixed)

Opened 9 years ago

Last modified 8 years ago

Add shapelet support to base Psf or Kernel classes

Reported by: jbosch Owned by: jbosch
Priority: normal Milestone:
Component: afw Keywords:
Cc: dubcovsky, jarvis, rhl, rowen, bick Blocked By:
Blocking: Project: LSST
Version Number:
How to repeat:

not applicable

Description

To support model-based convolution, we need a way to extract a shapelet representation from a Psf and/or Kernel. Several design questions:

  • Should this be part of Kernel or Psf? Right now, it fits most naturally as a ShapeletLocalKernel class attached to Kernel, but the whole LocalKernel API should probably be reviewed.
  • Where should policy information for converting images to shapelets live? Could it be attached to individual Psfs? Can arbitrary Psfs be required to supply additional information (such as a best-fit Gaussian sigma) that would otherwise have to be put in a policy?
  • What precisely do we mean by "shapelets"? We have choices with regard to normalization factors, Cartesian vs. polar, elliptical vs circular, multi-scale or not. Each of these could be specified by policy, by the Kernel/Psf?, or by the user of the Kernel/Psf?.

We could also defer this problem until after 1.2, and require galaxy modeling to use the native shapelet PSFs for now.

Change History

comment:1 Changed 9 years ago by DefaultCC Plugin

  • Cc rowen, bick added

comment:2 Changed 8 years ago by dubcovsky

The design that will be used is documented in the notes from the design review session. They can be found here:DM/SAT/DR-20110124-afw-multifit

comment:3 Changed 8 years ago by jbosch

  • Status changed from new to closed
  • Resolution set to fixed

Fixed in #1556 merge.

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