Changes between Version 10 and Version 11 of ppSubModifications_201009

Timestamp:

Oct 21, 2010, 7:23:22 AM (16 years ago)

Author:

eugene

Comment:

--

ppSubModifications_201009

@@ -66 +66 @@
 
 For the 20100918 version, there is still an arbitrary penalty term to bring the chi-square portion of the equation and the second moments portion into a common scale.   The equation is written in such a way that the minimization does not depend on either the number of stars used or the flux ratio of the two images.  The 4 different sets use 4 different penalty values.
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+20101021 UPDATE: after noticing problems with matched stacks, I discovered that single-convolution of simple images with ppSub was not able to produce a clean results as hotpants.  Looking at this closer, I discovered that the difference can be attributed to the use of the delta function kernel-zeroing technique of ppSub.  Switching to the Alard-Lupton technique of zeroing with the smallest kernel results in single convolutions which much more closely match the hotpants results.  When this is applied to DUAL convolution, the resulting differences are (a) much cleaner and (b) much less sensitive to the exact choice of kernels.  The 20101021 pages above use this improvement. 
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+The two images below compare a matched stack image generated with the 20100918 (left) and the 20101021 (right) versions of the PSF matching code
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+|| [[Image(matchedStack.v0.jpg)]] || [[Image(matchedStack.v1.jpg)]] ||