Summary of ppSub_testing_201201

Primary purpose is to wrap up and activate the convolution direction choice in ppSub.

Secondary purpose is to monitor if working as expected and address any additional issues (convolution troubles) and baseline to verify against any future changes in code (test set).

Background

Samples of previous information/work/comparisons

• ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/wiki/ppSub_vs_Hotpants
• ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/wiki/Basic_GPC1_Processing_IPP_Photpipe_Comparison

• ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/wiki/ppSubModifications_201009
  • ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/wiki/ppSub_Modifications_20101021.single
  • ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/wiki/ppSub_Modifications_20100918.single

• ​http://ps1sc.ifa.hawaii.edu/PS1wiki/index.php/TransientPhotfestSept2010
  • ​http://ps1sc.ifa.hawaii.edu/PS1wiki/index.php/Performance_Tests_July2010#A.X_Diffim_photometry_reprocessing_data_sample
  • ​http://ps1sc.ifa.hawaii.edu/PS1wiki/index.php/Diffimtest_IPP_photpipe_sne
  • ​http://ps1sc.ifa.hawaii.edu/PS1wiki/index.php/Diffimtest_ut100510_md07s056

Convolution direction choice

We want to avoid large deconvolution in PSF-matching image subtraction. As the image quality of the images continues to improve, always convolving the reference stack will not produce the best difference image and convolving the input image is desired. The quality of the difference image is evaluated in both directions and the better is chosen for the output (add specific details).

Current branch for testing the choice of convolution direction and is updated to r33098 (from 1/11/2012)

• ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/browser/branches/meh_branches/ppsub_test

Selected Test Samples

Initial test for if choosing the proper direction in stack-stack diffims now using MD04. Was initially done using MD10, but we want to continue to build up test samples over other IPP codes using MD04.

Start with just 2 skycells having example events from last year for photometry comparisons

055 --> 077.V2 -- center, 58 --> 073.V2 -- edge - qso and A star from last year

obsdate	stack_id	skycell_id	filter	FWHM_MAJ

Need tests to verify changes will not break diffims for other surveys (MOPS etc) but do not need to worry about magic now:

• simulated images
• warp-warp diffim - MD and 3PI TTI
• warp-stack diffim - MD and LAP stack

Difficult to use past examples of wrong convolution direction since refstacks remade, so select sample to just test current choices.

QUB exmples of wrong convolution choice

• ​http://star.pst.qub.ac.uk/ps1/psdb/userlist/10/
• ​http://star.pst.qub.ac.uk/ps1/psdb/userlist/5/?sort=-followup_flag_date

• ​http://star.pst.qub.ac.uk/ps1/psdb/candidate/1095456431022404400/

Not all seem to be due to convolving in the wrong direction and need to identify and separate the cases/causes if can.

CfA photpipe/HOTPANTs direction

Using single template/reference stack so locally get keyword CONVOL00 from header except slight issue with amps.

Monitoring

Nightly tests of convolution direction

Is there any conflict with the expected desired direction? Compare to CfA photpipe, detection counts.

• having IQ/FWHM keywords in stack images or at least the gpc1 DB would be helpful here since are calc for the PSF matching in the diffim

HOTPANTs comparisons

Difficult to automate, but are the diffims continuing to produce similar results.