This comparison involves matching northern and southern scans of seven 2MASS tiles:
1528 to 1534. Both datasets were obtained on February 13, 1999.
Sources were matched using the same criteria employed in comparison #2, save that all
sources with one or more of [jhk]_prg_flg = "fil" were excluded. This removed 90% of
the sample (almost exclusively sources fainter than the formal S/N=10 limits).
The above postscript files compare the mean Delta-mag for both
sets of scans of the six tiles in question. As before, the reference magnitude
scale is set by the northern observations.
The overall behaviour is similar to that found for tiles 1127-1132: there is
evidence for systematic offsets of <0.1 magnitude, notably in the J passband.
These fields are at relatively high latitude, so there are correspondingly fewer
bright stars.