General description: This file has the astrometry summary image QA information for a single run, in a compressed format. Essentially, it lists all filled pixels, with the mean value of the offset relative to the reference catalog for the pixel, and the number of stars contributing. This file serves as a useful intermediate file when generating the full image including all of the runs.
CAT: Reference catalogs that we compare to include: SDSS DR7 ("DR7"), 2MASS ("2mass"), USNO-B ("usnob"), UCAC-2 plus r14 ("ucac"), and UCAC-3 ("ucac3"). UCAC-2 only covers up to around declination of 40 deg; "r14" is an internal USNO product that was used to calibrated SDSS DR7. Finally, we compare to a version of the DR8 catalog that includes color corrections omitted in the official catalog ("sdssColor").
TYPE: We store the right ascension ("dra") and declination ("ddec") offsets for all catalogs. For "DR7" we also store the proper motion offsets ("dpmra" and "dpmdec"); we only compare proper motions for stars in the same run. For "sdssColor" we store an image of the DR8 proper motion field itself, for reference.
Note that the pixelization in this file is very high resolution (typically 9000 by 4500), but is downsampled (correctly) in some of the full images produced.
Naming convention: astromQAImage-CAT-TYPE-RUN.fits.gz
Approximate size: 500 kbytes.
File type: FITS
Read by products: photoop
Written by products: photoop
Required header keywords (HDU1):
Required column names: