There seems to be a bit of a nautical theme going on recently. After fishing for tadpoles, I’ve turned my attention to…um…well, a giant jellyfish. Which is surprising because I can’t stand fishing. It’s boring. You sit around under the stars, drink beer, have the occasional “interesting” thing happen and no sleep…oh wait, it sounds like I’m talking about astrophotography.
The Jellyfish Nebula (IC 443) is an extended source supernova remnant in the constellation Gemini, with a diametre of approximately 50 arc minutes. In comparative terms, the full moon has a diametre of 30 arc minutes, meaning that this nebula is about 2/3rds bigger than the size of the moon if you were able to see it with the naked eye.
I originally imaged this a couple of years ago with the modded Canon 450D, and although it was reasonable with only several hours of data, I was more interested in capturing it in narrowband, and putting the time into it that the Oiii bandwidth would require.
I’ve talked at length previously about imaging in narrowband, so I won’t go into it on this post. If you want to read more about my narrowband workflow then follow the link.
The Setup
This was our trusty DSO rig, consisting of the Skywatcher EQ5 Pro mount, Skywatcher 72ED refractor telescope, Altair Astro 183C Hypercam and Askar Duo Narrowband Filter, with images captured at unity gain (398 gain, 10 offset) in APT. Guiding was handled by PHD2 using a 9×50 finderscope and ZWO ASI120.
The Capture
This is one of those that I started several months ago but due to various reasons (weather being a large one), never got around to obtaining more data until recently.
So far I’ve managed three nights on this, with Millie contributing to the third night.
The Image (For Now)
The image as it stands right now is only 5hrs 15mins, so we could definitely use more time on it, especially to bring out the Oiii in it. But for what it is so far I’m pretty happy with the direction it’s going. For now though, with it disappearing from my location, that’s it for now until later in the year.
Millie has also had a go at processing the stacked data herself, with some guidance. I have to say that I’m pretty pleased with her version, especially for a first go. She used the stacked data, and processed it in line with the narrowband workflow I usually use.
My own version is okay considering the limited time put into it, but nonetheless I’m happy with it.
I’ll update this when I get some more time in later in the year, so for now thanks for reading, and clear skies all.
AstroHeart UK Photography 