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adrn / AchtungCoaddVerboten

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Computing positional chi-squared is wrong #7

Open adrn opened 12 years ago

adrn commented 12 years ago

For some reason, the measured position is always very close to the center of the pixel that the star is placed in. I think this is a problem with computing the chi-squared grid.

adrn commented 12 years ago

OK so because we're using the star image as our model, the measured offset should be close to 0.0,0.0 because the star image is offset the same as the noisy image! Instead, we will generate a new star model at each pixel center and then subtract and compute the chi-squared.