Pointing update

I believe I've completely dealt with the projection issues. There are a lot of new plots available now, pretty much everything for Jun/Jul 05 and July 07. Low on my to-do list is the rest of the pointing model tests. My conclusion now is that I can't match the 3-4" RMS in dAlt and dAz. Even with aggressive sigma-rejection of outliers, I only get down to ~10" RMS (which adds to ~15" RMS). My calculated pointing models differ significantly from Meredith's, but not extremely so for 0707. The code I've used to generate the plots is centroid_plots.pro under plotting/. Using that code, I am able to essentially reproduce each change made in do_the_pointing besides the distortion mapping. Because of the weak dependence of the pointing model on altitude, even errors on the scale of precession won't really hurt the pointing model calculations. The only unanswered question I think may be responsible for some errors - but not enough, I think - is whether eq2hor/hor2eq could be double-correcting for aberration and nutation, but this wouldn't affect the actual data reduction. It WOULD affect my plotting! I think my next test is to try to coadd different epochal data for particular fields, e.g. l001, l033. Not l000 because of the galactic coordinate issue.

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