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2011: NGC 7023; The Iris Nebula
Image details
Date: July 29, and 30, 2011
Exposure: 3 hours 10 min (38x 5 min), ISO 800, 18 Darks, 20 Bias, and 40 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 
Location: Die, France

High resolution: (2,27 Mb)
DSLR-LLRGB post-processing workflow  according to Scott Rosen's video tutorial:
 
Original RGB image in Nebulosity 2.5:
 -Color balance [CB]
 -DDP using standard settings [DDP]

Original CB/DDP RGB image in Photoshop CS3:
 -Carboni's v1.6 Vertical Banding Noise Reduction
 -Levels [Black-, Grey-, and White points]
 -Convert to greyscale [This creates the Synthetic Luminance]
 -Convert back to RGB [RGB reconvertion is only done for easy of interpretation of PS histgram and tools]
 
Synthetic Luminance in Photoshop CS3:
 -SmartSharpen entire image
 -Carboni's v1.6 Deep Space Noise Reduction [Removes noise from background, not DSO]
 -Curves, selective on weak dustlanes, with anchored background and highlights, 2x normal curve, followed by repair of contrast in highlights, in this case the center of the Iris, by a selective curve using layer masks,1x normal and 1x contrast curve
 -Screen Mask Invert to pull out the weak dust lanes even further from the backgroud
 -Highpass Filtering on the Iris'scenter using a layer mask
 -Shrink Stars using a minimum filter
 -Final tweaks on Luminance using Curves, especially in the Iris center
 
RGB processing in Photoshop CS3:
 -Curves and Levels to bring RGB to a comparable level as the Luminance
 -HLVG, medium strength
 -Carboni's v1.6 Space Noise Reduction
 -Carboni's v1.6 Less Crunchy, More Fuzzy
 -Increase saturation using Adam Block's method [3 copies of RGB, 3rd copy Luminosty blend mode, 2nd copy soft light blend mode, flatten all 3 copies] Repeat to taste, 3x for this image. This results in a slightly over saturated image
 -Luminance addition, blend mode Luminosity, at 50% opacity, flatten

 -Carboni's v1.6 Less Crunchy, More Fuzzy
 -Gaussian Blur (2px)
 -Increase saturation in Lab mode [Reds and Blues]
 -Increase saturation using Adam Block's method, 1x
 -Luminance addition on 100% opacity, Luminosity blend mode [The general idea is to increase the saturation of the RGB stepwise, until the luminance can be added at 100% opacity]
Old version

Image details
Date: July 29, and 30, 2011
Exposure: 3 hours 10 min (38x 5 min), ISO 800, 18 Darks, 20 Bias, and 40 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 
Location: Die, France

High resolution: (2,25 Mb)

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