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m (Testing PSF)
m (Testing PSF)
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Images are all of the same scale.
Images are all of the same scale.
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First row: (1,2,3) original image of saturated star centered
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First row: (1,2,3) original image of saturated star centered; the same image in (1,2,3) to better compare with the second row.
Second row: (1) PSF bmodel subtracted from saturated star; (2) PSF bmodel normalized to the maximum flux value of saturated star and then subtracted; (3) PSF bmodel normalized to the flux above 60000ADU that is limiting (black area is a consequence of over subtraction but spikes clearly appear)
Second row: (1) PSF bmodel subtracted from saturated star; (2) PSF bmodel normalized to the maximum flux value of saturated star and then subtracted; (3) PSF bmodel normalized to the flux above 60000ADU that is limiting (black area is a consequence of over subtraction but spikes clearly appear)

Revision as of 04:06, 24 April 2021

Contents

Stars

# Faint stars (19<=g<22): 41 in total. Median combined. Inner profile R[pix]<9, outer profile R[pix]< 200 and curve-of-growth up to 250 pix

# Bright stars (16<=g<19): 52 in total. Median combined. Inner profile R[pix]<9, outer profile R[pix]< 200 and curve-of-growth up to 250 pix

# Saturated stars (g<16): 29 in total.Median combined. Inner profile R[pix]<9, outer profile R[pix]< 200 and curve-of-growth up to 250 pix

Images in the 1st row: faint, bright and saturated star

Each image is 501 x 501 pix large ~ 200 arcsec x 200 arcsec (radius ~ 100 arcsec). Radial profiles and curve-of-growths given above.

Final PSF by average combining previous three images and scaled to median

Central part of the saturated star masked during combining.


Joining stars

Points from SMA>10 & SMA < 20 are used to create an overlap region for fitting: (1) inner region of saturated star is replaced by bright, unsaturated star; (2) full extent of the PSF

Testing PSF

Images are all of the same scale.

First row: (1,2,3) original image of saturated star centered; the same image in (1,2,3) to better compare with the second row.

Second row: (1) PSF bmodel subtracted from saturated star; (2) PSF bmodel normalized to the maximum flux value of saturated star and then subtracted; (3) PSF bmodel normalized to the flux above 60000ADU that is limiting (black area is a consequence of over subtraction but spikes clearly appear)

Adding spikes

Images: (1) PSF true size 2000 x 2000 pix; (2) bright star with spikes normalized to the max intensity of the PSF and (3) sum of PSF[central 500x500] and a bright star.

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