WSClean Version 1.7

Released 2015-03-10

Summary: Deconvolution can be performed with a compressed sensing method (MORESANE) and clean masks are now supported. Also, determining the restoring beam size by fitting the psf is now the default; previously this was only done when -fitbeam was specified.

Besides new features, version 1.7 has a long list of bugfixes so I recommend everyone to update.

Full list of changes:

  • MORESANE Compressed sensing deconvolution using J. Kenyon’s python MoreSane implementation.

  • Cleaning now supports cleanmasks, either with a casa file (-casamask) or a fits file (-fitsmask).

  • Fitting a Gaussian to the PSF is now the default for determining the restoring beam size.

  • Added convenience parameter -intervalsout to make fits snapshot movies.

  • Added option -no-update-model-required to skip writing the model column when possible, which speeds up -mgain<1 runs that include reordering.

  • Added option -saveweights to store the gridded weights as fits file.

  • Bugfix: Samples which were gridded at v=0 were slightly downweighted in uniform/briggs weighting due to one-off bug in (inverse-symmetric) weighting grid. This could manifest itself in a PSF which was slightly less aesthetically pleasing, although in most cases it is hardly noticeable (especially in cleaned images).

  • Bugfix: In multi-scale mode, there was half a pixel offset in restored structures.

  • Bugfix: Rare time-rounding error, causing incorrect DATE-OBS value in output fits files. Reported by D. Kaplan.

  • Bugfix: Bug causing infinite continuing cleaning in joined channel cleaning when ending on negative component.

  • Bugfix: Image weight keyword is incorrectly converted to int, leading to possible MFS images with NaN values. Reported by R. van Weeren.

  • Bugfix: WSClean used REFERENCE_DIR instead of PHASE_DIR for image centre, giving incorrect coordinates when NDPPP was used for phase shifting (SF #30). Reported by R. van Weeren.

  • Bugfix: Crashes when cleaning near the horizon, caused by incorrect bounding box calculation during restoring (SF #33). Reported by S. Bourke.

  • Bugfix: When specifying multiple measurement sets with different bands, frequency keyword now represents central frequency.

  • Bugfix: Fixing FITS keyword bug; WSClean used to write ‘Hz’ in CUNIT4 (the ‘Stokes’ dimension). Reported by M. Iacobelli.

  • Textual: Help on -beamsize parameter said default unit is arcmin, but since 2.5 it is actually in arcsec (when not specifying a unit). Reported by M. Iacobelli.

These bugs were fixed after internal releases:

  • Bugfix: Fixing bug in masked cleaning causing spurious components.

  • Bugfix: Honour cleaning border when using masks and in single pol mode (SF #32).