The story of Dragon : Okay, then not, then okay again ? Long story …
Flying Dragon Nebula - Sh2-114
A challenge was to get clear skies. Another one would be to catch the Dragon.
The path (or the journey) is always a good story. The three Ws : When Where Why (and not the 3 Ys, Why Why Why, that’s for other businesses).
Last week of May and early June, I drove 2000 kilometers. The 1000s to drive back were awful, rain, rain and rain again.
I got the opportunity to meet my fellows astrophotographers from my astronomy club for the first time, and it was supposed to happen on the 7th of June so few days after my drive back earlier. The place chosen was great (South of France, some altitude, good skies expected). Though, after my terrible drive in the rain, and some weather forecast telling me it’s not gonna be an easy travel, I decided to cancel my attendance.
Anyway, I spotted an excellent place a year ago, with very low light pollution (Bortle scale 2, meaning artificial light being half of the natural light. Correction : I am wrong on this statement : most probably 2,5 squarred times the natural light, but it is a great sky already) and Meteoblue was giving me clear skies at this place on the Thursday 6th of June. I was excited, I loved this place … so quiet, peaceful and far away from everything. I decided to go there, an hour drive through the country.
Once there, the sky was marvelous and I took my flats with the Sun going down … at least, real and good flats calibrations frames, I’m not doing that often. Waiting now for the dark, expecting the few clouds to move away. As soon as I spotted Vega, it was a matter of minutes to catch Polaris for my polar alignement … yep, done !
I waited until midnight, as the weather forecast was telling me “Clear skies at 12” … well, it didn’t happen. Clouds happened, a lot of them, big ones, I went for multiple targets to catch, but the results remained the same : here it is, nope it disappeared … Time for me to pack back all my stuff and forget about it. Severals deers, several foxes, a hare in a village … wild nature was there, just not the skies.
I also got that at my place top of the hill, on the 7th of June, skies were expected great. A bit skeptical from my previous day forecast, I decided that the drive is about 10 minutes so I would regret not trying it.
Well, I have to admit that the two pictures of the different places at a different day are showing that my second day was going to be ideal.
No cloud, not a single one ! So why the Flying Dragon Nebula ? Well, I got this object in mind for a long time. First, because it is beautiful. Second, because there is a story about a Dragon and a Unicorn that I like (if you want, you can check out the comic named “Stuffed”). And finally, because it is very very faint, I mean … a good challenge.
I was so excited, and so scared that the weather would change that I started to shoot around 11PM (way too early, not really dark yet). I stayed there for 4 hours of shooting.
Let’s talk about the shooting a bit. I’m using N.I.N.A. software but I never really shot a target with the sequencer automating the different steps. Based on the very few hours of clear skies I got, I couldn’t imagine driving back with no picture at all because I would have missed something in my script. But this time, I thought I was prepared enough to use the sequencer. I have been inspired by Laura who shifted from the AsiAir to N.I.N.A. because she has hosted her setup far away. I used her sequencer to create mine.
Because this object is very faint, I thought it would be good to expose more for each picture. Without a guiding system, I used to expose 40 to 50 seconds per frame, with a guiding system I went up to 180 seconds but I felt I needed more. I decided to expose 300 seconds per frame. I have this feeling about exposing long : if something is going wrong during the exposure (wind, guiding errors …) then I will get a 5 minute shot useless. While doing 5 frames with lower exposure, I would loose only one frame … Nevertheless, I decided to go for 300s exposure per frame.
I waited quietly 4 hours in my car, checking every single picture coming in … I got huge guiding errors (maybe my guide star was too low and the dithering was pushing it out of the frame … I need to investigate on that), but at the end the stacking phase with Pixinsight gave me an interesting and good final frame.
I have this feeling that using the minimum number of processes for post-treatment would affect less the quality of the final picture. And after some tryouts, I’m okay with my final version with less stars (using Bill Blanshan scripts)
Exifs : Celestron C9 + Hyperstar / PegasusAstro Nyx-101 / PlayerOne Poseidon C Pro cooled at -10°C / Askar D1 HaOIII filter / Guiding System Askar 135mm scope with PlayerOne Ceres C
51 lights 300 seconds each - 48 selected for stacking (4 hours exposure for final shot)
20 biases - 20 darks - 50 flats from the day before.
Stacked with Pixinsight (WBPP)- Post-Treatment with Pixinsight with a minimum of processes (7).
