It's been a long time coming but I've always wanted to do this: Shooting in narrowband and then adding RGB stars. Occasionally I was joined by
@Martin Reh for the imaging sessions which then also served as an introduction to kstars.
It took very careful processing to make the combination of the starless narrowband image work nicely with the stars extracted from the RGB data. Additionally, either the refractor suffers a bit from CA towards the blue or the blue filter is transmissive towards the UV. Reducing the resulting blue halos was quite a challange. In the future we will check for both possibilities.
Of course, because of its brightness, the Eastern Veil Nebula is a great target to try such an endeavor. However, it is known to not show a lot of emission of SII, therefore I decided on a bicolor HOO palette for the narrowband data. Hydrogen was mapped into the red channel, Oxygen into the green one and the blue channel is a mixture between 85% of the OIII emission and 15% of the Ha emission, resulting in the cyan parts of the nebula.
I hope I did the target justice.
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