Discovered for many inputs into ppStack (i.e., deep and even refstacks), that the PSF in the output convolved stack grows with the number of inputs beyond the initial target PSF. Had been missed due to convolved stacks really only being used for magic, but was noticed with some M31 analysis and deepstacks of MD04.

Other issues:

• hard limit on number of inputs (solved: descrip to watch for)
• heavy RAM use
• change the target PSF FWHM selected

Branch for testing (currently r32161 from last summer -- need to update..) -- ​http://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/browser/branches/meh_branches/ppstack_test

• many outputs turned on (runs slower, makes many many files)
• ppStackMatch.c -- need add a TESTING2 for reading in already processed conv images..
• ppSubMatchPSFs.c has TESTING but not ifdef at start, is a .DEBUG. used to trigger?

Test Sets

More easily setup than for testing ppSub, need a large number of a variety of inputs and some number of similar inputs.

MD04

Sample of 20 and 100 drawn from the the MD04.V3 GR0 deepstack set.

• FWHM in stack logs.. add how compare to psphot? need to add histogram of both actual inputs

Batch scripts for running in /data/ipp059.0/mhuber/testppstack_deep201111/MDdeeptest

Sim

A small variety set of many groups for 20 and 100 inputs. Also sample of two similar inputs using the _000 and _001 images.

Simtest setup:

• pixelscale 0.258"/pixel?

filename	sim FWHM	FWHM_MAJ (pixel)	IQ_FW1 (pixel)
image.0	1.0	3.82	2.98
image.1	1.1	4.19	3.28
image.2	1.2	4.58	3.62
image.3	1.5	5.69	4.49
_and repeat_

Batch scripts for running in various /data/ipp059.0/mhuber/testppstack_deep201111/ppstack_simdeep* (needs cleanup)

Tests

• do clean simulated images suffer the same problem?
  • can use for more detailed testing since faster to run than MD04 skycell and not particular to GPC1 data
• how is it related to the range of inputs and number
  • is 20 inputs enough to reveal problem, if 100 then will be tedious
• what are the output convolved images being stacked, what is the target the images are being convolved to
• need to understand what the code does, so first test is to look at each output, add others and step through the code...

Sim

20 input case: 4 groups

filename	sim FWHM	sim FWHM_MAJ	log Input FWHM (pixel)	log kron (pixel)	conv FWHM	conv IQ_FW1
_000	1.0		3.82(1)	1.99/92,88/78,05/05,91/81
_001	1.1		4.19(1)	2.19/09
_002	1.2		4.58(1)	2.55/48
_003	1.5		5.69(1)	3.11/00

• input FWHM 4.57+/-0.72 (average or median?)
• target seeing FWHM: 5.70 -- set by worst input, kron ~3.1

filename	FWHM_MAJ (pixel)	IQ_FW1 (pixel)
real_000
real_003
fake_000
fake_003
conv.1
conv.3
comb.initial
stack

20 input case w/ similar inputs: 10 groups

filename	sim FWHM	sim FWHM_MAJ	log Input FWHM (pixel)	log kron (pixel)
_000	1.0
_001	1.1

• input FWHM 4.07+/-0.19 (average or median?)
• target seeing FWHM: 4.28 -- set by worst input, kron ~2.26

100 input case: 25 groups