PSP QA for run 3813, rerun 41

QA produced on Mon Aug 25 17:51:50 CDT 2003 with photo version v5_4_25

	Field Quality (nFields=540)
quality	nOK	nHOLE	% HOLE
union	539	1	0.2
col. 1	540	0	0.0
col. 2	540	0	0.0
col. 3	540	0	0.0
col. 4	540	0	0.0
col. 5	540	0	0.0
col. 6	539	1	0.2

PSP status plot

PSF width (FWHM arcsec) statistics for column 6, filter r:
Mean PSF width = 1.49
Median = 1.51, min = 1.05, max = 1.92
There are 0 fields ( 0.0%) with PSFwidth > 4.0 arcsec
This run is 540 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	0.35	0.13	0.03	0.05	0.02
col. 2	0.30	0.08	0.03	0.04	0.03
col. 3	0.27	0.07	0.03	0.03	0.02
col. 4	0.32	0.06	0.03	0.03	0.03
col. 5	0.35	0.07	0.03	0.04	0.03
col. 6	0.35	0.11	0.03	0.01	0.02

PSP status plot

	Mean N stars for estimating PSF
band	u	g	r	i	z
col. 1	21.5	35.2	40.8	38.0	45.1
col. 2	22.1	36.0	41.7	38.9	43.9
col. 3	22.3	37.4	43.3	40.2	44.3
col. 4	21.7	36.7	42.8	40.0	44.2
col. 5	21.2	38.2	43.5	41.8	44.5
col. 6	23.2	38.7	44.4	41.5	46.3

Number of stars used for estimating PSF

	Mean m(aperture)-m(psf) Bias (mag)
band	u	g	r	i	z
col. 1	-0.05	-0.05	-0.04	-0.05	-0.05
col. 2	-0.05	-0.05	-0.04	-0.05	-0.06
col. 3	-0.05	-0.05	-0.04	-0.05	-0.06
col. 4	-0.05	-0.05	-0.04	-0.05	-0.05
col. 5	-0.05	-0.05	-0.04	-0.05	-0.05
col. 6	-0.06	-0.06	-0.05	-0.05	-0.06

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	0.02	0.02	0.02
col. 5	0.02	0.02	0.02	0.02	0.02
col. 6	0.02	0.02	0.02	0.02	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	22.43	22.12	21.23	20.58	19.38
max	22.54	22.21	21.30	20.70	19.52
min	22.07	21.52	20.94	20.27	19.24

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	0.01	0.00	0.01	0.00	0.02
col. 2	0.01	0.01	0.00	-0.01	-0.05
col. 3	0.01	-0.02	-0.03	-0.01	-0.03
col. 4	0.02	-0.00	0.00	0.01	-0.02
col. 5	0.00	0.03	0.01	0.01	0.05
col. 6	-0.04	-0.02	-0.00	-0.00	0.03

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	1.01	1.03	0.99	1.06	1.03
col. 2	0.76	0.99	1.04	1.04	1.07
col. 3	0.96	1.04	0.97	1.09	1.04
col. 4	0.88	1.01	1.05	1.07	1.12
col. 5	0.93	1.07	0.96	1.00	1.04
col. 6	0.93	1.02	1.04	1.07	1.02

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).