On the night of Jan 21, 2022 I’d scheduled 2 targets, as with other evening this is not a case of being too greedy but rather a necessity given my local horizon restrictions. The two main subjects this night were Rosette and Jellyfish Nebula, I have recently “finished” my Rosette and the first Mosaic attempt had included a panel of the Jellyfish. I saw this opportunity to capture more data on both of these objects. I decided to switch between the two subjects and divide the night in half rather than getting what would otherwise have been 1 hour on Jellyfish at the end of the evening.
At the end of the night I had managed the following, all taken with my modified DSLR at ISO800 with the Optolong L-Enhance filter:-
Rosette (NGC2237) – 119 2m = 3h 58m Integration
Jellyfish (IC443) – 154 2m = 5h 8m Integration
30 2m Darks and 30 Flats were taken the following morning.
Post Processing
My intention with this data was to begin adding multiple nights data together for each target. I had already had 2 session this winter season on the Rosette and 1 on the Jellyfish (as part of my first mosaic attempt). For each of the subjects I ran Deep Sky Stacker using it’s file groups to put each nights’ set of files in their own group, any common files (for example if the same ISO had been used across all nights in the case of Bias) I would put in the Main Group tab.
Mid Stacking…notice the groups at the bottom, Main group contain common files, Group 1, 2, 3 in this case contain there separate nights sessions on this target each with their own Lights / Darks and Flats. Group 4 Empty – DSS creates an empty group as you add tabs.
Adding multiple nights together got me the following totals:-
Rosette (NGC2237), Total 9h 56m Integration
Jellyfish (IC443), Total 9h 18m Integration
Rosette (NGC2237)
As mentioned above I’ve now got almost 10hours of integration on this subject. I think during the stacking of this I noticed that most of the “best” images were from a single night. Best here is based on DSS’s score/FWHM and Number of Stars. As my previous post seem to show more data is key. However, although the 4 hours of data on this night I think has smoothed out the image and reduced the noise a little from the previous session I think there are diminishing returns. I think my next session on this target will need to focus more on the quality than adding time, slowly pushing up the average FWHM and Score figures. That said here is my latest with 9h56m.
Final Rosette January 2022
Jellyfish (IC443)
A much fainter proposition this one, needs more data than the total of 9h18m of this image. Noise is apparent due to the stretching of the data. I’ve added some colour boost (Vibrance and Saturation layers) to the nebula alone after creating a starless version using Starnet+. Here’s the starless and final version of the Jellyfish.
Starless Jellyfish January 2022
Final Jellyfish 2022
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