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Changes between Version 22 and Version 23 of Durham_MDS_Testing

v22	v23
56	56	Here is a comparison of the PSFmags from the cmf files of four adjacent (arbitrarily chosen) MD07 stacks with SDSS model mags. r-band on the left, g-band on the right. 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 r-band stellar locus also appears tighter in cell 41 than in the other r-band cells. As the are no extended source magnitudes in the cmf files, all the galaxies (black open circles) are offset.
57	57
58		[[Image(MD07_rband_sdss.jpg, 600px)]] [[Image(MD07_gband_sdss.jpg, 600px)]]
	58	[[Image(MD07_rband_sdss_v2.jpg, 600px)]] [[Image(MD07_gband_sdss.jpg, 600px)]]
59	59
60	60	Here is a image of part of the above r-band mosaic of four stacks, with sextractor detections in green. Interestingly, the skycells have gaps between them (I thought they would overlap slightly?), and one of the cells has many more detections. The reason for the latter is not clear. The pixel-pixel noise and background levels are indistinguishable from the other three - the only difference appears to be in the structure of the background (Jim's mottling effect). Note also the dark halos around bright objects where the background subtraction has been too aggressive.