Terapix Star Formation Region IC 1396, © 2002 CFHT
RC3 / PGC catalog version 1.1
930x5 multi-band SDSS galaxy images from the RC3 catalog, with morphological information
by - Updated April 24th, 2006

This archive contains
-  PGC-1.1.txt : a subset of the RC3 catalog observed with the Sloan Digital Sky Survey (SDSS) release 3 in ASCII format. Morphological types and Hubble types are listed for each galaxy.
-  fits/ : images in FITS format [http://fits.gsfc.nasa.gov/] extracted from the SDSS release 3 in the 5 bands u',g',r',i' and z'.

  • The original images around PGC galaxies were obtained directly from the SDSS DAS server
  • All g, r and i images were checked by eye, and a dozen of galaxies with very incomplete coverage or with large positional offsets were excluded from both the catalog and the set of images.
  • All galaxies were then automatically background-subtracted, resampled and rescaled to 255x255 (using SWarp with Lanczos3 interpolation), in such a way that the blue isophote at mu=25 mag.arcsec^-2 fits right into the central half of the frame. This was done by setting the output pixel scale to 12.0*dexp(log D25)/256 (log D25 is given in the RC3 catalog). This is twice the width of the previous release.
  • All g, r and i images were checked by eye, and about a dozen galaxies were removed from the archive because of incomplete coverage or strong contamination by satellite trails in g, r or i. There are 930 galaxies remaining. Note that u and z were not checked visually, hence some strong artifacts might be present in these bands.

-  png/ : colour images in PNG format generated with STIFF. All images have the same scale in surface brightness.
-  PGC-1.1.jpg : a colour poster containing all PNG images pasted together using montage

Important: this preliminary set of small galaxy images is for testing purposes, mostly image decomposition and galaxy classification through machine learning. All images have been background-subtracted and brought to a common scale to simplify dimensional reduction. This means that the Point Spread Function varies a lot from one image to the next.

Please note that these data are currently for use within the EFIGI collaboration only, and should not be redistributed without prior consent of the author (E.B.).

PGC-1.1.tar.gz - 3.6 kb
1.2 GB
Poster - 1.5 kb
2.4 MB

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