Background on images

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== Background from boxes (1D) ==
== Background from boxes (1D) ==
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Background is the mean value from boxes 32 x 32 pix large, inside which all objects are masked. Also, the mean standard deviation is estimated from the boxes.  There are several cases: Mean=bkg, (stdev), mean-stdev=bkg1m, mean+stdev=bkg1p, mean-3*stdev=bkg3m, mean+3*stdev=bkg3p == 9.58, (4.72), 4.85, 14.30, -4.59, 23.74
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Background is the mean value from boxes 32 x 32 pix large, inside which all objects are masked. Also, the mean standard deviation is estimated from the boxes.  There are several cases plotted in the radial profile plot: Mean=bkg, (stdev), mean-stdev=bkg1m, mean+stdev=bkg1p, mean-3*stdev=bkg3m, mean+3*stdev=bkg3p == 9.58, (4.72), 4.85, 14.30, -4.59, 23.74
[[Image:boxes.png]]
[[Image:boxes.png]]

Revision as of 11:46, 14 April 2021

mask = segmentation_map > 0 # Sextractor's segmentation mask with DETECT_THRESH  =  1. and ANALYSIS_THRESH =  1.
bkgmask = (data == 0.0)  # Mask of the outer parts of the image without data (blank part)
mesh_size=[50, 100, 150, 200, 300, 500]
percent = [1, 7, 10, 15, 25, 26]
sigma_clip = SigmaClip(sigma=3.)
bkg_estimator = MedianBackground()
bkg = Background2D(data, (mesh_size, mesh_size), filter_size=(5, 5),mask=mask,coverage_mask=bkgmask,sigma_clip=sigma_clip,bkg_estimator=bkg_estimator,exclude_percentile=percent,fill_value=0.0)

Image:icl50.png

Image:icl100.png

Image:icl150.png

Image:icl200.png

Image:icl300.png

Image:icl500.png

Background from boxes (1D)

Background is the mean value from boxes 32 x 32 pix large, inside which all objects are masked. Also, the mean standard deviation is estimated from the boxes. There are several cases plotted in the radial profile plot: Mean=bkg, (stdev), mean-stdev=bkg1m, mean+stdev=bkg1p, mean-3*stdev=bkg3m, mean+3*stdev=bkg3p == 9.58, (4.72), 4.85, 14.30, -4.59, 23.74

Image:boxes.png

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