Changes between Version 1 and Version 2 of GalacticPlane_and_wBand_20140526

Timestamp:

May 26, 2014, 1:51:18 PM (12 years ago)

Author:

eugene

Comment:

--

GalacticPlane_and_wBand_20140526

@@ -9 +9 @@
 This improvement will also help diff operations in the plane.  For the bad pair of exposures from Larry, the old parameters resulted in many skycells having 30-60k diff detections (due to dipoles).  the new parameters generally keeps the numbers close to 10k.  
 
-The following figures illustrate the astrometry failure and the diff detections.  
+The following figures illustrate the astrometry failure and the diff detections.  I added the exposures to a DVO database, calibrated first with the original configuration.  I then calculate the astrometric residuals between the pairs of detections.  I also generated a DVO database with the images calibrated using the new psastro parameters.  The left image shows (as a density histogram) the astrometric residuals as a function of the magnitude.  The right image show the same measurement for the new calibration.  
 
-[[Image(dense.20120524.g.png,700px)]]
+|| [[Image(sample.dPos.v0.png,700px)]] || [[Image(sample.dPos.v1.png,700px)]] ||
+
+Aside from the overall tighter distribution, the left hand plot has a small excess of detections with w-band magnitude < ~21 and astrometry residual > ~0.2 arcsec.   Selecting these detections and plotting them on the sky over the chip outlines gives the left-hand plot below.  Adding as red dots all of the diff detections from this pair of exposures gives the right-hand plot.
+
+
+|| [[Image(astrom.out.png,700px)]] || [[Image(diff.det.png,700px)]] ||
+