PSP QA for run 7016, rerun 40

QA produced on Wed Oct 17 23:34:26 CDT 2007 with photo version v5_4_28b

	Field Quality (nFields=326)
quality	nOK	nHOLE	% HOLE
union	325	1	0.3
col. 1	325	1	0.3
col. 2	326	0	0.0
col. 3	326	0	0.0
col. 4	326	0	0.0
col. 5	326	0	0.0
col. 6	326	0	0.0

PSP status plot

PSF width (FWHM arcsec) statistics for column 6, filter r:
Mean PSF width = 1.30
Median = 1.29, min = 1.15, max = 1.73
There are 0 fields ( 0.0%) with PSFwidth > 4.0 arcsec
This run is 326 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	0.56	0.10	0.03	0.03	0.04
col. 2	0.45	0.08	0.03	0.03	0.03
col. 3	0.49	0.04	0.02	0.02	0.01
col. 4	0.31	0.07	0.02	0.02	0.03
col. 5	0.38	0.05	0.01	0.02	0.02
col. 6	0.29	0.06	0.01	0.02	0.01

PSP status plot

	Mean N stars for estimating PSF
band	u	g	r	i	z
col. 1	9.4*	30.7	38.1	36.2	39.7
col. 2	18.2	31.9	40.1	36.2	39.8
col. 3	11.5	34.7	42.7	39.2	43.0
col. 4	18.5	33.0	42.8	39.6	41.5
col. 5	16.7	34.0	43.8	42.4	41.6
col. 6	19.1	34.5	45.4	42.6	45.5

*Red entries are triggered by Nstars < 10
Number of stars used for estimating PSF

	Mean m(aperture)-m(psf) Bias (mag)
band	u	g	r	i	z
col. 1	-0.04	-0.03	-0.03	-0.04	-0.04
col. 2	-0.03	-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	-0.03	-0.04
col. 6	-0.03	-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	0.02	0.02	0.02	0.02	0.02
col. 2	0.02	0.02	0.02	0.02	0.02
col. 3	0.02	0.02	0.02	0.02	0.02
col. 4	0.02	0.02	0.01	0.02	0.02
col. 5	0.02	0.02	0.01	0.02	0.02
col. 6	0.02	0.02	0.01	0.01	0.02

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	20.88	20.64	20.33	19.79	18.75
max	20.97	20.74	20.43	19.95	18.92
min	20.66**	20.32**	19.70**	19.17**	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	0.00	0.00	0.00	0.02
col. 2	-0.02	-0.01	-0.01	-0.03	-0.07
col. 3	-0.00	-0.00	-0.02	0.00	-0.03
col. 4	0.01	0.01	0.02	0.02	-0.01
col. 5	-0.00	-0.01	0.00	-0.01	0.03
col. 6	0.01	0.01	0.01	0.02	0.05

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	0.99	1.00	0.99	1.06	1.04
col. 2	0.93	0.98	1.02	1.02	1.06
col. 3	1.05	1.02	0.98	1.06	1.04
col. 4	0.95	1.02	1.06	1.02	1.08
col. 5	1.02	1.05	0.98	0.98	1.04
col. 6	0.94	1.01	1.03	1.05	1.01

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).