This is my first attempt at a narrowband image. I bought a new mono camera this summer (ASI178MM) and some 3nm Astrodon filters. Right now, I only have H-alpha and OIII, but SII is on my shopping list.

I decided to delve into the world of narrowband because of the growing light pollution problem in my area. I'm in a Bortle 5 area, which isn't too bad, but I live about 3 miles from the interstate, and they are building a lot of new businesses to the south which is ruining my skies. Last year, they built a new shopping center Kroger and Academy Sports. This year, they are building another shopping center right next to it (Hobby Lobby and TJ Maxx). Next year they are planning to build a new car lot, complete with lights burning all night long. So desperate times call for desperate measures.

Obviously it took me a long time to research how to do this properly. I had some issues figuring out the proper gain and offset for the new camera, and from shooting this image, I ultimately decided that the settings I chose were not so great. I also had to figure out how to do this in PixInsight, which was the longest part of the process, and something I'm still working on perfecting. I had to give up Deep Sky Stacker for good and process completely in PI so I would have total control over the stacking and integration processes.

The noise on this camera is amazingly low. On the other hand, the Amp glow is quite extreme. I had to figure out the proper technique to remove it using dark subtraction. That ate up a lot of time. I also had some clusters of hot pixels that looked like stars in the dark frames. When I posted my darks on the forums for people to review, they actually thought I had taken my darks outside at night with the lens cap off! That's how much these bizarre artifacts looked like stars. Another disappointment about the ASI178 is that it did not come with a built-in USB hub. I bought it from Highpoint Scientific and a few months after I got it, I discovered that all new cameras being produced by ZWO comes with a USB hub. So I missed the boat. Nevertheless, I still think its a good camera for what I'm doing. Obviously the ASI1600 is superior, but the 178 has very small pixels (2.4 microns) which is the smallest I've been able to find available anywhere, which was quite appealing for my pixel scale.

I really wish the image had turned out better, because I found it to be too dim and not as colorful as I would have liked. Some of the stars are also a bit oblong, and I'm not sure why this happened. I did my best to cull the images that had bad stars. But with 600 second subs, it was difficult to sacrifice them. I used Morphological Transformation to shrink them down a little and help to hide the oblong shapes, but "pixel peeping" reveals they are still a bit hazy which reminds me of some shots I've seen with doublet refractors.