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Sample Galaxies

• I had a look at 3 following cases. I have done photometry with and without sky subtraction. It seems that the sky has been already subtracted and turning off the sky subtraction does not change the results that much. Therefore, I think that we can ignore the sky subtraction part for now.

• Another issue that I notices is that the outer region of the galaxies, and across the entire field (the whole image) the sky average level is negative. I don't know what that means for now, however its a problem where the growth curve drops down at a certain point.

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• This is the case that Pan_STARRS and SDSS are completely consistent. Even though the center of the galaxy is saturated in the PS image, it still gives a reasonable result. (Left/Top: with sky subtraction - Right/Bottom: without sky subtarction)

Image(pgc5284.jpg), 700px Image(pgc5284_skySubtracted.jpg), 700px

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• This case appears fainter in all PS images. (Left/Top: with sky subtraction - Right/Bottom: without sky subtarction)

Image(pgc40516.jpg), 700px Image(pgc40516_skySubtracted.jpg), 700px

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• This case appears brighter in g-band PS image. (Left/Top: with sky subtraction - Right/Bottom: without sky subtarction)

Image(pgc93031.jpg), 700px Image(pgc93031_skySubtracted.jpg), 700px

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