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Hi allI have standard star data that I would like to use on some analysis, and enc. What would be the best method, to use the data? (After went through and trown all the bad data out)1) Determine the magnitudes for the individual frames, and then using a mean or avg value.
2) Or stacking the frames, and then determining the magnitude once-off?Thanx
Pat

Hi Pat,I'll start by saying that I'm not a photometrist but have an unnatural compulsion to answer any question asked 8-)That said, the answer probably depends on what type of science you want from the results and whether you're planning to do aperture or PSF photometry. Remember, the individual frames were probably taken with a variety of exposure times, seeing conditions and airmasses even if it was the same instrument. My guess would be that averaging the individual reductions would give you a better answer overall but I could easily be convinced otherwise. Some quick googling came up with a similar question (and answer) posed at http://www.physics.nau.edu/~pmassey/Mosaicphot.html The spoiler from the link: do it both ways and see which works best for you.Cheers,
-Mike