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Aug 2

I was working with MDF data but not I'm switching over to NCP data. For MDF data, I have been able to identify a common set of stars (with low errors in all passbands and no nearby objects) and collect data about them over time (from the IPP data). I identified two objects to be identical if they are within 1 pixel of each other, but that condition seems to be too tight (I'm not getting much data at all) and I'm going to relax this to 5 pixels. This shouldn't be a problem because the stars are not supposed to have any neighbors within 20 pixels. The code for that is currently running and might take some time. I have also written code for plotting data, but right now there isn't much to plot because I set the identification condition to be too tight.

Anyhow, I'm pretty sure the code is working, so I'm going to go ahead and look at the NCP data. Identifying a common set of stars from that data is probably going to be more difficult because we don't have stacked images, but my idea now is to look for a few "good" images taken in photometric conditions and identifies the stars from there. Will try this tomorrow.

Data access on Odyssey:

1. Run JAuth.jar to get login key
2. ssh -Y into to odyssey.fas.harvard.edu, or herophysics.fas.harvard.edu, using the electronic key. 
3. run tcsh
4. source .myrcstubbs
5. data are at /n/panlfs/data/MIRROR/ps1-md/gpc1/
6. nightly science uses individually warped images, nightly stacks run on stacked frames
7. image types: wrp is warped. 
8. see available modules with "module avail"
9. load a module with "module load hpc/ds9-5.6"
10. photometry is in .cmf files, as FITS tables. 
11. in python: 
    1. import pyfits as p
    2. p.open('filename')
    3. print a[0].header
12. or, imhead on command line
13. a[1].data.AP_MAG for aperture magnitudes
14. PSF_RA and PSF_DEC are in the skycell files. 
15. make a scratch directory for data in /n/panlfs

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