PSP QA for run 6464, rerun 40

QA produced on Thu Jul 17 11:23:48 CDT 2008 with photo version v5_4_28b

	Field Quality (nFields=162)
quality	nOK	nHOLE	% HOLE
union	32	130	80.2*
col. 1	64	98	60.5*
col. 2	66	96	59.3*
col. 3	74	88	54.3*
col. 4	66	96	59.3*
col. 5	142	20	12.3*
col. 6	71	91	56.2*

*Red entries are triggered by the percentage of unacceptable fields exceeding
5 in any column, or 15 for the union of all columns.
PSP status plot

PSF width (FWHM arcsec) statistics for column 6, filter r:
Mean PSF width = 2.10
Median = 2.15, min = 1.56, max = 3.50
There are 0 fields ( 0.0%) with PSFwidth > 4.0 arcsec
This run is 162 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	0.76	1.56	1.89	1.79	1.04
col. 2	0.62	1.63	1.85	1.93	0.88
col. 3	0.59	1.59	1.73	1.81	0.92
col. 4	0.63	1.72	1.76	1.79	0.81
col. 5	0.65	0.64	0.47	0.55	0.35
col. 6	0.64	1.77	1.84	1.78	0.83

PSP status plot

	Mean N stars for estimating PSF
band	u	g	r	i	z
col. 1	35.0	7.9*	5.5*	5.9*	19.1
col. 2	54.2	7.1*	6.5*	6.2*	19.4
col. 3	41.5	7.9*	6.9*	6.0*	21.6
col. 4	60.9	7.7*	6.6*	6.2*	23.9
col. 5	76.0	30.4	26.5	28.9	54.7
col. 6	62.7	7.4*	6.6*	6.6*	22.5

*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	-0.10	-0.12*	-0.11*	-0.10*	-0.12
col. 2	-0.12	-0.13*	-0.11*	-0.11*	-0.10
col. 3	-0.09	-0.14*	-0.10*	-0.10*	-0.09
col. 4	-0.11	-0.14*	-0.11*	-0.10*	-0.09
col. 5	-0.09	-0.10*	-0.10*	-0.10*	-0.10
col. 6	-0.10	-0.17*	-0.15*	-0.12*	-0.11

*Red entries are triggered by
apCorr Bias ( 0.15 0.10 0.10 0.10 0.15) mags in (u g r i z)
Aperture Correction Bias plot

	Mean m(aperture)-m(psf) Error (mag)
band	u	g	r	i	z
col. 1	0.02	0.11*	0.14*	0.08	0.05
col. 2	0.02	0.06	0.07	0.16*	0.02
col. 3	0.02	0.02	0.14*	0.14*	0.02
col. 4	0.02	0.03	0.22*	0.14*	0.02
col. 5	0.02	0.01	0.01	0.01	0.01
col. 6	0.02	0.03	0.10*	0.06	0.02

*Red entries are triggered by
apCorr Error > ( 0.15 0.10 0.10 0.10 0.15) mags in (u g r i z)
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	20.14	19.06	18.48	16.89	17.84
max	21.04	19.79	18.56	17.59	18.42
min	19.94**	18.77**	18.24**	16.71**	17.63**

**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	0.30*	-0.10	2.25*	0.04	-0.13
col. 2	0.08	0.11	-0.76*	0.27*	0.10
col. 3	-0.20*	0.24*	0.22*	-2.07*	-0.40*
col. 4	0.05	0.19*	0.65*	2.84*	-0.74*
col. 5	0.57*	-0.70*	-1.80*	-1.31*	0.87*
col. 6	-0.79*	0.27*	-0.56*	0.23*	0.31*

*Red entries are triggered by abs(offset) > 0.15 mag

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	1.14	1.14	1.25	1.09
col. 2	0.95	1.13	1.21	1.26	1.13
col. 3	1.04	1.15	1.16	1.28	1.11
col. 4	0.94	1.15	1.26	1.24	1.18
col. 5	1.04	1.19	1.15	1.21	1.12
col. 6	0.98	1.15	1.19	1.28	1.10

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).