PSP QA for run 3650, rerun 20

QA produced on Thu Feb 6 17:56:33 CST 2003 with photo version v5_3_58

	Field Quality (nFields=127)
quality	nOK	nHOLE	% HOLE
union	113	14	11.0
col. 1	126	1	0.8
col. 2	119	8	6.3*
col. 3	127	0	0.0
col. 4	124	3	2.4
col. 5	125	2	1.6
col. 6	126	1	0.8

*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 = 1.57
Median = 1.54, min = 1.31, max = 2.07
There are 0 fields ( 0.0%) with PSFwidth > 4.0 arcsec
This run is 127 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	0.52	0.30	0.06	0.14	0.07
col. 2	0.60	0.30	0.06	0.06	0.06
col. 3	0.46	0.17	0.05	0.05	0.02
col. 4	0.44	0.25	0.04	0.04	0.06
col. 5	0.46	0.31	0.04	0.05	0.09
col. 6	0.55	0.26	0.02	0.01	0.06

PSP status plot

	Mean N stars for estimating PSF
band	u	g	r	i	z
col. 1	17.0	32.7	40.6	39.9	37.0
col. 2	18.9	35.4	44.6	37.3	36.6
col. 3	18.0	37.9	43.3	38.1	39.4
col. 4	20.2	36.3	41.1	38.2	37.1
col. 5	20.1	39.4	42.0	39.0	38.9
col. 6	21.8	39.4	43.8	40.4	43.4

Number of stars used for estimating PSF

	Mean m(aperture)-m(psf) Bias (mag)
band	u	g	r	i	z
col. 1	-0.07	-0.06	-0.05	-0.05	-0.06
col. 2	-0.06	-0.06	-0.05	-0.06	-0.07
col. 3	-0.06	-0.06	-0.05	-0.05	-0.06
col. 4	-0.06	-0.06	-0.05	-0.05	-0.06
col. 5	-0.06	-0.06	-0.05	-0.05	-0.06
col. 6	-0.07	-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	0.03	0.03	0.03	0.02
col. 2	0.02	0.04	0.03	0.02	0.02
col. 3	0.02	0.03	0.02	0.02	0.02
col. 4	0.02	0.03	0.03	0.02	0.02
col. 5	0.02	0.04	0.03	0.02	0.02
col. 6	0.03	0.04	0.03	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	22.67	22.33	21.20	20.22	18.91
max	22.72	22.39	21.23	20.27	19.01
min	22.43	21.85	21.16	20.16	18.84

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	0.04	0.01	0.01	0.02	0.04
col. 2	-0.00	0.00	-0.00	-0.02	-0.05
col. 3	0.03	0.00	-0.01	-0.00	-0.02
col. 4	0.02	0.01	0.01	0.01	-0.01
col. 5	-0.01	-0.02	-0.00	-0.01	0.00
col. 6	-0.07	-0.01	0.00	0.00	0.04

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	1.03	1.05	0.98	1.05	1.04
col. 2	0.77	1.00	1.06	1.03	1.06
col. 3	1.00	1.05	1.00	1.09	1.03
col. 4	0.85	1.03	1.06	1.04	1.08
col. 5	0.93	1.07	0.98	0.99	1.04
col. 6	0.86	1.03	1.04	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).