Quality holes in DR1 coverage

The following is a reference note on quality of fields, including hole fields in the DR1 data set.

Each field of DR1 has a quality set. This quality is determined by the seeing of the field, the tracking of the stripe, the cloudiness of the data (photometric or not), and whether or not the photometric pipeline timed out while processing.

The quality is designated by an integer from 0-5, and is stored in the quality parameter of the tsField*.fit file for each field. Here's a key to what that quality means.

 0=UNDETERMINED,   // The data has been obtained, however its
                   // quality has not yet been determined.
 1=BAD,            // Bad data.  Don't bother with it.
 2=ACCEPTABLE,     // The data is acceptable for the survey, but we would
                   // like to improve on it.
 3=GOOD,           // The data is fully acceptable for the survey, and
                   // there is no need to improve it.
 4=MISSING,        // The data is missing, but we include the area of
                   // sky associated with the data as a hole in the
                   // survey.
 5=HOLE            // The data is unacceptable, but we include the area
		   // of sky associated with the data as a hole in the
		   // survey.

Also in the tsField file are more details on exactly why quality was set to what it was.

For instance, if the tsField file has a frames_status value of 3 = FIELD_TOO_LONG, meaning the field timed out during processing, this results in a quality = 5 (HOLE) for the overall field quality.

The psp_status is also available in the tsField file, as are the culled, badmask,acceptablemask,goodmask and holemask masks.

We note that there are different holes in the best version of sky than the target version. This is due to the photometric pipeline timing out for a number of fields processed with pipeline version v5_3. By the time we realized we were getting significantly more timeouts from this new version, we increased the allowed time per field from 2 hours to 4 hours (a normal field takes 5 minutes or less), but didn't catch all the fields we could. In other words, if we had let these run longer, they may have finished successfully. Future data releases will include these data.

The timeouts are almost always on fields with very bright stars or flares (from the edge) in them.

There are also some holes where photo finished ok; in these cases (where the frames_status is 0), some other problem with the quality, generally either a short non-photometric patch of sky or astrometric wobble, inclines us to set a range of fields to hole.

Fields which are marked as hole will show up as holes in the large scale structure masks; objects detected in those fields are not included in the data release. The following table lists the holes in the DR1 fields.

Target skyVersion holes

run rerun camcol fieldstart-end 'quality (5=hole)' 'frames_status (3=timeout,0=ok)'
-------------------------------------------------------------------------


1737 0 6 30 	 5 3
1889 1 4 42 	 5 3
1895 0 1 170-185 5 0
1895 0 1 268-285 5 0
1895 0 2 170-185 5 0
1895 0 2 268-285 5 0
1895 0 3 170-185 5 0
1895 0 3 268-285 5 0
1895 0 4 170-185 5 0
1895 0 4 268-285 5 0
1895 0 5 170-185 5 0
1895 0 5 268-285 5 0
1895 0 6 170-185 5 0
1895 0 6 268-285 5 0
1992 0 1 141   	 5 3
1992 0 1 168     5 0
1992 0 2 130     5 3
2074 0 5 174     5 3
2126 0 4 278     5 3
2126 0 6 341     5 3
2248 0 1 186-196 5 2
2248 0 2 186-196 5 2
2248 0 3 186-196 5 2
2248 0 4 186-196 5 2
2248 0 5 186-196 5 2
2248 0 6 186-196 5 2
2328 0 1 77      5 3

Best skyVersion holes

run rerun camcol fieldstart-end 'quality (5=hole)' 'frames_status (3=timeout,0=ok)'
-------------------------------------------------------------------------


752 20 2 205 	  5 3
752 20 2 276-277  5 3
752 20 5 692 	  5 3
752 20 6 660 	  5 3
756 20 1 390      5 3
756 20 2 587      5 3
756 20 3 338      5 3
756 20 4 162      5 3
1035 20 5 40      5 3
1035 20 6 112-113 5 3
1043 20 6 149 	  5 3
1140 20 2 131 	  5 3
1140 20 6 250-251 5 3
1231 21 3 195     5 3
1231 21 6 141-142 5 3
1331 20 5 141     5 3
1331 20 5 75      5 3
1345 21 2 607     5 3
1350 22 2 442-443 5 3
1359 21 3 60      5 3
1412 20 3 315     5 3
1450 20 6 71      5 3
1458 20 3 646     5 3
1458 20 4 674     5 3
1462 21 2 349     5 3
1462 21 2 568     5 3
1462 21 4 585     5 3
1462 21 4 670     5 3
1462 21 5 88      5 3
1462 21 6 399     5 3
1462 21 6 457-458 5 3
1729 21 1 266 	  5 3
1729 21 1 373     5 3
1729 21 3 195-196 5 3
1729 21 5 281     5 3
1737 20 3 115     5 3
1737 20 6 30-31   5 3
1740 21 2 135     5 3
1740 21 2 95      5 3
1740 21 6 54      5 3
1895 21 1 270-280 5 0
1895 21 2 270-280 5 0
1895 21 3 270-280 5 0
1895 21 4 270-280 5 0
1895 21 5 270-280 5 0
1895 21 6 270-280 5 0
1896 20 5 109     5 3
1992 20 2 130     5 3
2075 20 2 48      5 3
2076 20 1 140-141 5 3
2125 21 1 132     5 3
2125 21 5 80      5 3
2126 21 4 278     5 3
2126 21 6 341     5 3
2131 21 6 25-26   5 3
2137 21 2 279-280 5 3
2137 21 3 243     5 3
2137 21 3 267     5 3
2137 21 6 183     5 3
2189 20 3 57      5 3
2190 21 1 144     5 3
2207 20 6 60      5 3
2243 20 1 130-131 5 3
2243 20 4 130-131 5 3
2247 20 1 285     5 3
2299 20 1 299-300 5 3
2299 20 3 283     5 3
2305 20 3 38-39   5 3
2305 20 4 65      5 3
2326 20 2 299     5 3
2326 20 2 309-310 5 3
2328 20 1 122     5 3
2328 20 1 77-78   5 3
2328 20 2 175     5 3
2328 20 4 38      5 3
2335 20 6 74      5 3
2662 20 2 257     5 3
2738 20 4 155     5 3
2738 20 4 184-185 5 3
2738 20 4 280     5 3
3325 20 1 196     5 3
3325 20 1 354     5 3
3325 20 1 362     5 3
3325 20 1 430     5 3
3325 20 3 246     5 3
3325 20 3 483     5 3
3325 20 4 99      5 3
3325 20 5 345     5 3
3325 20 5 470     5 3
3325 20 6 287     5 3