(c)2015 Robert J Hawley. Some Rights Reserved.I thought it would be useful to record what I did. As is my current practice the first thing I do is build masks. After combining the colors I extract a luminance. I then make a copy and HT it. Most of the star masks are based on the linear version. The bright, midtones, and shadows masks are based on the non linear with stars removed. The bright mask was built using ACDNR on the non linear
| Tool | Mask | Reason |
| Channel Combination | Combine source images. Each had been separately mosaic | |
| Fits Header | Add the WCS coordinates to the file. The linear L was used for the solution. | |
| Color Calibration | ~star mask | Using a carefully chosen sample area for a white reference I increased the amounts of red and blue relative to green |
| Curves | bright mask | increase the color saturation of the bright areas |
| Curves | star mask | remove any color from the stars |
| HistogramTransformation | make the image non-linear. | |
| HistogramTransformation | remove some of the pedestal in the image | |
| Curves | bright mask | tweek the saturation more |
| HDRMultiscaleTransform | bright mask | Using Linear 3 I increased the contrast between light and dark areas. Linear 3 gave the most interesting result |
| Curves | bright mask | Increase the brightness of the bright areas |
| Curves | midtones | Try to bring up the midtone areas. This was not enough and I retried later with a fancier mask |
| MultiscaleMedianTransform | bright mask | sharpen the image by selectively increasing certain wave sizes and applying noise reduction |
| DarkStructureEnhance | A script that increases the contrast of dark features | |
| TGVDenoise | shadows | reduce the noise in the shadows |
| HistogramTransformation | shadows | further darken the shadows |
| PixelMath | Sadar halo | Sadar was pretty blown out at this point. Replace it with the non Linear L image |
| Curves | Color Mask | Sadar had a purple halo. Color mask is a new script that searches for a particular color range and builds a mask for it. In the case of my images stars tend to get purple halos. Most were prevented using star masks, but that did not work for Sadar and a couple of other bright stars. Thus by carefully selecting colors I built a mask for this and other halos. I then partially desaturated these leaving some of the color (since I liked the effect). |
| Curves | bright mask | I wanted to increase the midtones. To prevent loss of contrast I first increased the brightness of the bright areas |
| Curves | midtones2 | Using a carefully constructed mask I increased the midtones in the range of the feathery nebula and also did a mild increase of the some of the dimmer midtones |
| TGVDenoise | midtones2 | Doing these increases increased the noise. I used TGVDenoise in Lab mode to apply noise reduction to the chrominance without affecting the detail of the luminance |
| Curves | shadows | some more reduction of the background to increase contrast |
(c)2015 Robert J Hawley. Some Rights Reserved.