| | 56 | Here is a comparison of the PSFmags from the cmf files of four adjacent (arbitrarily chosen) MD07 stacks with SDSS model mags. Blue indicates an object flagged as a star by SDSS. I haven't rejected any images flagged as defective in any way, so this probably explains the blue points offset by 2 mags. Clearly the zero-point varies from cell to cell (do we expected this? after all, no calibration has been done as far as I can tell). The stellar locus also appears tighter in cell 41. As the are no extended source magnitudes in the cmf files, all the galaxies (black open circles) are offset. |
