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Subject
M106
Date
24th January 2004
Telescope or Lens
Vixen ED102SS
Mount
G11
Camera
SXV H9
Filters
TT LRGB NIR Blocker
Total Exposures L 120 min R 20 min G 20 min B 20 min
Sub exposure

6 x 10 min

3 x 20 min

2 x 10 min
2 x 10 min
2 x 10 min
Binning
Luminance 1 x 1 RGB 2 x 2
Field of view and resolution
2 Arcsec / Pixel
Comments  
This was my first go at combining colour in photoshop and it seemed to work well.
The 16 bit tiff frames require some considerable contrast stretching to bring out the detail. Care must be taken not to go too far, and to use several iterations to achieve the desired result. Also do not move the end points but use the curve. If the centre becomes too bright you can lasso the area and with an appropriate amount of feather darken the area to bring out detail. Finally convert to 8 bit mode to add the luminance to the RGB. The image is somewhat smaller than the camera field of view as I needed to do a median flip for the mount between the colour and luminance frames. This led to some misalignment and a smaller image. Image also shows galaxy NGC 4248 and another very faint galaxy to the left that I have yet to identify. Other than that I think the DDP was slightly over done and the luminance exposure could need a bit longer at the f ratio of 6.5.