Widefield image of a Cepheus region with special interest in Van den Bergh 152 (vdB 152, also known as Cederblad 201), the blue reflection nebula on the right-center and DeHt5 (PN G111.0+11.6) the planetary nebula on the bottom (a bit on the left), but including many other interesting objects: LBN538, B175, LBN528…
A few weeks ago I saw a nice Apod image of this field in HaRGB. As I had imaged it in the past but in RGB only, I decided to add some Hydrogen alpha data next summer. But before doing this, I have tried to improve my RGB image.Top right, you can see my 2010 image, as it is posted on my website. It was made with a set of Baader filters that produced very strong halos (in fact, this was the last image with the Baader filters: I changed them for Astrodon filters). The thing is that because of the halos and that at that time I didn't know any better, I stretched it very little.
I have tried to improve the image with the new tools available in PixInsight and also with what I have learned over the years. You can see the result bottom right.
The main processing differences are:
1. Using Local Normalization (within WBPP): obtained a linear image with lower FWHM, lower Eccentricity and also lower noise.2. Stretching with GeneralizedHyperbolicStretch: smaller final size of the stars (and their halos).
3. Separation into large-scale and small-scale components: to process them separately and highlight nebulosities.
4. Use of MMT as noise reduction tool.
Click on the images for a full size version, or go to the Gallery section for complete exposure details.
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