From: Frank Masci <fmasci@ipac.caltech.edu>
Subject: Re: sca(m)n 44525a
Date: May 1, 2014 at 11:04:59 AM PDT
To: Sherry Wheelock <slw@ipac.caltech.edu>, Carl Grillmair <carl@ipac.caltech.edu>, Timothy Conrow <tim@ipac.caltech.edu>, Roc Cutri <roc@ipac.caltech.edu>


Further to this, the mag range was now limited to 7 < w2mpro < 11.5. This places more emphasis on the bright mags. The spatial pattern is the same as before, hence the gradient is not flux-dependent (no surprise). This was also confirmed by Sherry.

Attached is another way of looking at it. The black crosses are measurements with Y-pixel position < 50.

Regards, Frank



On May 1, 2014, at 9:51 AM, Frank Masci <fmasci@ipac.caltech.edu> wrote:
Decided to take a closer look at scan 44525a - one of the scans exhibiting a spatially dependent photometric bias. I’m trying to get a product to better compare with the flat-field calibrations.

Attached is a 2D map of the binned median in K - w2mpro color. There are about 120-150 points per bin. I limited the mag range to 7 < w2mpro < 13.5, but still, the median is being dominated by the more numerous faint sources. This is seen in the second plot where the blue dots are binned medians +/- a robust rms.

Note also the deviation of ~0.03 mag from the zero-color line.

f.y.i. - the pattern in this 2D map is qualitatively consistent with Sherry’s AllWISE comparison from yesterday:
http://wise2.ipac.caltech.edu/proj/slw/NEOWISER/V75test/V75test_ALLWISEvsxy/W2_allwise-V75test_vsy_44525a.jpg

Regards, Frank

<2massK-w2mpro_2Dbinmed.pdf>
<2massK-w2mpro_density.pdf>

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ubject: neowiser-allwise 2D plots
Date: May 14, 2014 at 11:53:33 AM PDT
To: Roc Cutri <roc@ipac.caltech.edu>, Tim Conrow <tim@ipac.caltech.edu>, Sherry Wheelock <slw@ipac.caltech.edu>, Davy Kirkpatrick <davy@ipac.caltech.edu>, Sergio Fajardo-Acosta <fajardo@ipac.caltech.edu>, Chris Gelino <cgelino@ipac.caltech.edu>, Carl Grillmair <carl@ipac.caltech.edu>


If anyone is interested, here’s a montage of all the 212 scan-level-qa w?mpro(neowiser - allwise) 2D plots from ops.v7.5, created by Tim.

There are 3 (w1+w2) x 3 (w1+w2) plots per page. Sorry, you’re not supposed to view the fine print, but glean their overall qualitative appearance.

http://wise2.ipac.caltech.edu/proj/fmasci/neowiser_L1bMdex-FPAdep/allfops_v7.5_dw12_vs_xy.pdf

The pattern is consistent across scans, with W2 showing a gradient along the bottom-left/top-right diagonal and with a slight tendency for fluxes to be relatively brighter at bottom left.

Regards, Frank