A set of 37 light frames of M1 along with 20 dark, 20 flat, 20 flat dark, and 20 bias frames were collected using a 203mm TMB APO at F7 and SBIG ST-10 with 5nm AstroDon H-alpha filter. Flat and flat dark frames were 1 second exposures. The flat frames were taken during the day using a uniform gray or blue part of the sky. Detailed processing of the initial light, flat, dark, flat dark, and bias image set is demonstrated by the CCD Automatic Image Set Processing example.

The goal is to enhance the stacked image for display on the web.


Initial stacked image






Step 1

Digital Development brightness and contrast increase.






Step 2

A soft 3x3 Gaussian blur is used to smooth the image and fill the 8 bit histogram so that all gray values are displayed.






Step 3

10 iterations of ARL with a 5x5 Gaussian PSF is used to sharpen the stars and M1.






Step 4

3 iterations of background smoothing.






Step 5

Levels is used to set the black and white points.






Step 6

The histogram is expanded using a uniform histogram modification.






Step 7

A soft 3x3 Gaussian blur is used to smooth the image and fill the 8 bit histogram so that all gray values are displayed.






Step 8

Full resolution crop of M1.






M1 H-alpha full resolution crop. 31 x 8 minute with ST-10, 5nm AstroDon Ha filter, and 203mm TMB APO at F7.






Step 9

Scale the image by 0.5 for display on the web.






M1 H-alpha full resolution scaled for web display.






Unlimited undo redo process history of M1 H-alpha.




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