Four-pane mosaic of North America Nebula and Pelican Nebula

[BrendanC]

Hi all

Finally finished this one - a four-pane mosaic going from the North America Nebula across to the Pelican Nebula. Culmination of the eight clear nights we had during July in the UK, and literally hours and hours of trying to get it to work. I've never done a mosaic of a nebula before and it was a very steep learning curve (yes, another one).

* 17:39 hours of integration at ISO800 from 120x120s + 37x180s + 177x240s subs, over 8 nights (had to use different exposure times to cope with light pollution and varying Moon phases)
* Bortle 4 sky, Moon average 60% phase, 27° height
* Calibration: 25 flats, 25 dark flats, 50 darks
* Hardware: Sky-Watcher 130PDS scope (F5), Sky-Watcher NEQ6 mount, Canon EOS1000D DSLR camera with IR filter removed, Sky-Watcher 0.9x coma corrector, Datyson T7C guide camera, Angel Eyes 50mm guide scope
* Software: Polar alignment with SharpCap Pro, guiding with PHD2, capture with Astrophotography Tool (APT), stacking with Deep Sky Stacker (DSS), post-processing with StarTools, Photoshop CS2, Affinity Photo and Topaz Denoise AI

Cheers, Brendan

Edited August 5, 2021 by BrendanC

[etsatlo]

Wow. Just wow

Firstly for the results which are stunning. 

And secondly for your patience!

Bravo

[old_eyes]

Very, very nice indeed. I can't see the joins. A;ways a good start for a mosaic. Lots of detail and depth when you look at the full resolution image as well.

[Lee_P]

I really like this. The mosaic approach has let you get a cracking composition.

[tomato]

Cracking mosaic. Did you use any specialist processing software to stitch the panels together? I couldn’t get anything as smooth as this without using the likes of APP or the PI scripts.

[BrendanC]

It was a real pain. I initially thought it would make sense to stitch the unstretched panels, then post-process them in StarTools. I planned to do this in Microsoft ICE, until I found out it had disappeared! I found a copy online, but then it either wouldn't recognise the overlaps, or if it did, I couldn't control which bits of which panel to use. In the end I found it was best to process the panels first, then stitch them together, using Affinity Photo. It has a nice panorama feature that allows control over masking, so I could tell it which bits of which panel I wanted 'on top' as it were, then it did a good job of colour-balancing everything and rendering it. So, now I know, but I wish I'd known before trying, over and over again, using different stacking algorithms, different software, different orders of doing things, starting again, trying again, etc etc etc. Basically there are 999,999,999,999 ways of doing this wrong, and I found all of them. On the 1,000,000,000,000th attempt, I got it right.

[tomato]

Total respect for dedication to find away through. When I took the plunge and purchased a PI license and then hardly used it I thought what a waste of money, but then  @Laurin Dave introduced me to the photo metric mosaic script and it was worth buying just for that.