2018-04-18 LBN 552, LDN 1228 Cooperation, Session from 05.04.2018 - 18.04.2018

And also in the following days April was a lot of fun. Quiet and sunny weather during the day, then waning moon at night and many clear nights. The right time for a molecular cloud. I would not have had the idea to photograph LDN 1228 and LDN 552 alone, the suggestion came from Marcel Drechlser, with whom I had already successfully photographed Sh2-174 in a cooperation. We arranged a cooperation on short notice. Marcel was to contribute the luminance and I the color.

This only made sense, because Marcel's sky at about 900 m above sea level is darker and more transparent than mine by far - if the weather is right. Therefore, its luminance should provide the details and depth. My RGB images would make the picture more colorful. To cover as large a field as possible, I used my Epsilon with 430mm focal length.


As expected, Marcel's luminance at f2.2 and ASI 1600 MMC after 13.5 hours of RASA was overwhelming:


My color photos after 18.5 hours of Epsilon at f3.3 suffered so much, it's unbelievable:


How could these different results be sensibly combined? Our stars also had different spike angles. The solution could only lie in the basic processing without stars. So I first removed the stars from the RGB and then pushed the colors clearly. The not yet so respectable interim result looked like this:


We did the same with the luminance. The combination of starless color and starless luminance already offered a different image:


Here you can suddenly see the details and a pleasant colour. Now only the stars had to go back in. First I inserted the RGB stars from my Epsilon images and overlaid them with those from the luminance. We had eight spikes on the bright stars. Since Marcel's spikes are much thinner than mine from the Epsilon (he creates them artificially by a cross of threads over the optics), I retouched the thick spikes star by star, so that only the thin spikes remained. A pagan job, but it was worth it.


The finished result is here ...