The dark nebula Barnard 344 in the Cygnus complex was already longer on my list. In the middle of August the conditions were favorable enough to start the project. The very colored region should be exposed with H-alpha and RGB - luminance then delivers the H-alpha. The processing of the data turned out to be more difficult than expected, because the very bright star Sadr from outside the image came in between.
For although Sadr was far from my image field, the star caused a huge reflection - presumably at the filter edges. In H-Alpha it was not really noticeable, in RGB therefore a lot more. I decided to keep the picture field and to expose through the complete night. The reflection unfortunately not went away afterwards through processing.
So, in the next clear night, I decided to move the field a bit to see if the reflection would be disappeare. That worked out - but I had to turn about 30% of the field to the east. That would move Barnard on the right edge, but what else could I do? After the second night RGB (this time without reflection) I processed the version without reflection into the overall picture and could finally win a usable RGB raw image.
H-Alpha Version of the first night:
RGB raw image of the second night with reflection:
RGB raw image after stacking the 2nd and 3rd night:
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