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2013: Messier 27; The Dumbbell Nebula in HaHa(HaR)GB
Image details
Date:  June 10, 11, July 5, 6, 7, 8, and 9, 2013
Exposure: 19 hours and 40 min total; H-alpha, 9 hours 40 min (29x 20 min), ISO800, 12 Darks, 30 Flat darks, 30 Flats; RGB, 10 hours (60x 10 min), ISO800,
12 Darks, 20 Bias, and 30 Flats

Telescope: 8" Skywatcher Newton
@F/5 with MPCC 
Mount: NEQ6-pro, controled by EQmod/CdC, guided by  QHY5/9x50 Finder Guider/PHD
Camera: Peltier-cooled Canon 350Da (TEC@10C)
Location: Emmen, The Netherlands

High resolution: (2,81 Mb)
DSLR-LLRGB post-processing luminance work flow  according to Scott Rosen's video tutorial, and Starizona's Ha(HaR)GB method:
 
Ha-data:
Original 32-bit floating point RGB image in Photoshop CS3:
 -In Chanels fill green and blue chanels with black
 
-Convert RGB image to 16-bits greyscale
 -Convert back to RGB [RGB reconvertion is only done for easy of interpretation of PS histgram and tools]
 -Star repair
 -Levels to set white point
 -GradientXterminator (med/low, and fine/medium)
 -Levels to set black point
 -Curves (anchored background and highlights)
 -Carboni's v1.6 Deep Space Noise Reduction [Removes noise from background, not DSO]
 -Levels correction for background blackpoint
 -High pass filtering on the details in M27 (8px overlay & 40px soft light; Don Goldman method)
 -Curves (anchored background and highlights)
 -Levels correction for background blackpoint
 -Carboni's v1.6 Deep Space Noise Reduction [Removes noise from background, not DSO]

RGB data:
Original 32-bit floating point RGB image in Photoshop CS3:
 -Convert image to 16-bits
 -GradientXterminator (med/low, and fine/medium)
 -Levels to set black point
 -Make duplicte image for Luminance processing

Convert Luminance image to grey scale and back to RGB
 -Curves (anchored background and highlights)
 -Carboni's v1.6 Deep Space Noise Reduction [Removes noise from background, not DSO]
 -High pass filtering on the details in M27 (8px overlay & 40px soft light; Don Goldman method)
 -Levels correction for background blackpoint

Continue processing RGB image
 -Curves (anchored background and highlights)
 -Increase saturation using Adam Block method, 3x
 -Selective color, Reds (-100% Cyan), Yellow (-100% Cyan), Blue (+100% Cyan, -100% Yelllow), 50% opacity
 -Insert luminance at 100% with layer mask to only add detail to the core of M27

HaRGB combine in Photoshop CS3:
 -Register and align in DSS 3.3.2
 -Extract R-channel from RGB image and paste on top of Ha image, normal blending, 30% opacity, HaR30
 -Paste HaR back to R-channel in RGB image to form (HaR30)GB image
 -Stretch (HaR30)GB, keeping an eye out on overal starcolor in the image to keep as close to original RGB image
 -Increase saturation by Adam Block method, 3x
 -Color balance using curves
 -Insert Ha in luminosity blend at 30% opacity
 -Color balance using curves
 -Insert Ha in luminosity blend at 60% opacity, with layer mask to only add to outer halo
 -Levels (blackpoint restoration)
 -Tweak color balance with levels and curves


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