PSP QA for run 7150, rerun 40

QA produced on Wed Dec 19 14:24:12 CST 2007 with photo version v5_4_28b

	Field Quality (nFields=180)
quality	nOK	nHOLE	% HOLE
union	176	4	2.2
col. 1	178	2	1.1
col. 2	180	0	0.0
col. 3	179	1	0.6
col. 4	178	2	1.1
col. 5	179	1	0.6
col. 6	180	0	0.0

PSP status plot

PSF width (FWHM arcsec) statistics for column 6, filter r:
Mean PSF width = 1.44
Median = 1.40, min = 1.29, max = 1.78
There are 0 fields ( 0.0%) with PSFwidth > 4.0 arcsec
This run is 180 fields long.
PSF width plot for all 30 chips
PSF width derivative plot for all 30 chips

	Mean PSP status (0=OK)
band	u	g	r	i	z
col. 1	0.10	0.11	0.12	0.22	0.02
col. 2	0.03	0.14	0.14	0.15	0.02
col. 3	0.04	0.12	0.14	0.18	0.01
col. 4	0.01	0.16	0.15	0.19	0.02
col. 5	0.00	0.14	0.14	0.15	0.04
col. 6	0.00	0.15	0.12	0.14	0.01

PSP status plot

	Mean N stars for estimating PSF
band	u	g	r	i	z
col. 1	41.8	36.0	34.2	30.8	59.5
col. 2	73.1	33.9	35.5	31.1	60.7
col. 3	51.1	33.7	36.4	30.2	60.8
col. 4	81.4	33.7	39.1	30.4	63.7
col. 5	70.0	34.1	37.2	31.7	52.3
col. 6	82.4	34.8	42.4	36.4	63.0

Number of stars used for estimating PSF

	Mean m(aperture)-m(psf) Bias (mag)
band	u	g	r	i	z
col. 1	-0.05	-0.03	-0.04	-0.04	-0.04
col. 2	-0.04	-0.03	-0.03	-0.04	-0.04
col. 3	-0.03	-0.03	-0.03	-0.03	-0.04
col. 4	-0.03	-0.03	-0.03	-0.03	-0.04
col. 5	-0.03	-0.03	-0.03	-0.04	-0.04
col. 6	-0.04	-0.03	-0.03	-0.04	-0.04

Aperture Correction Bias plot

	Mean m(aperture)-m(psf) Error (mag)
band	u	g	r	i	z
col. 1	0.01	0.01	0.01	0.01	0.02
col. 2	0.02	0.01	0.01	0.01	0.01
col. 3	0.02	0.01	0.01	0.01	0.02
col. 4	0.02	0.01	0.01	0.01	0.01
col. 5	0.02	0.01	0.02	0.01	0.01
col. 6	0.02	0.01	0.01	0.01	0.01

Aperture Correction Error plot
A few related auxiliary plots:
Aperture Correction Scatter (w/o bias contribution)
Power-law index for the outer PSF
Kolmogoroff exponents

*Averaged over 6 columns

	Sky brightness* (mag/arsec2)
band	u	g	r	i	z
mean	22.15	21.77	20.47	19.76	18.54
max	22.31	21.90	20.73	20.03	18.83
min	22.02	21.32	19.73**	19.41	18.37

**Red entries are triggered by
min Sky < ( 21.2 21.0 20.0 19.2 18.0) mag in (u g r i z)
Sky brightness (in counts) plot
Sky brightness (in mag/arcsec2) plot
Sky derivative plot
Sky colors plot

	Mean Sky Column offsets
band	u	g	r	i	z
col. 1	-0.00	-0.03	-0.02	-0.01	0.01
col. 2	0.03	-0.01	-0.01	-0.03	-0.07
col. 3	0.03	0.00	-0.01	0.00	-0.03
col. 4	-0.01	-0.00	0.01	0.00	-0.02
col. 5	0.02	0.02	0.02	0.00	0.05
col. 6	-0.06	0.02	0.02	0.02	0.07

The noise is estimated from the width of the sky histogram, corrected
for the dark variance, and normalized by the Poisson value:
norm. spurious noise = sqrt[gain*(sigma_sky^2-dark_var)/sky]
Values significantly larger than 1 indicate the presence of spurious noise.

	Spurious Noise (from sky quartiles)
band	u	g	r	i	z
col. 1	1.00	1.09	1.02	1.11	1.05
col. 2	0.77	1.01	1.08	1.07	1.07
col. 3	0.99	1.06	1.02	1.11	1.05
col. 4	0.91	1.07	1.10	1.07	1.09
col. 5	0.95	1.11	1.00	1.02	1.05
col. 6	0.89	1.05	1.08	1.10	1.03

Spurious Noise plot
Note that bright stars cause single-field spikes which are, for
different bands, aligned in the field number. A temporal increase
in noise can be traced in the r-i-u-z-g order (2 fields shift).