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On the Bias Jumps » History » Version 1

Eli Rykoff, 10/31/2013 04:00 PM

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h1. On the Bias Jumps
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-Eli Rykoff
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Something strange is going on with the bias jumps at 2048...
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I'm taking as an example 180985, CCD 41, somewhat arbitrarily.
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I use swarp to subtract the sky and rebin to a 2" scale to highlight the sky levels.  This is the finalcut image which shows the problem:
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|!{width=750px}180985_41_finalcut.jpg!|
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But if we go back to the raw_obj image (same scaling) which has had DECam_crosstalk run on it then it looks fine!  (Well, it could use a good flat-fielding).
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|!{width=750px}180985_41_raw_obj.jpg!|
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Similarly, the raw-raw image looks fine (though it's hard to get the scaling right because of the dynamic range).
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So this is being inserted into the image somewhere along the line...Alex suspects the flat field...