They are releasing five variants of their cooled series (based on already available uncooled versions with similar specs). A quick visit to http://astronomy-imaging-camera.com/ will let you sort through those variants. Each carrying one of the latest Sony sensors, these cameras all excel at high speed planetary imaging. Cooling adds an interesting dimension here, though. Could these cameras pull double duty as a deep sky imaging camera? Initial tests on uncooled versions showed promise and I was eager to find out.
I’m a fan of ZWO cameras and that’s no secret. I have an ASI120MM which was one of ZWO’s first cameras to market. It was excellent for planetary imaging when first released. I had very good success with mine and it also served well as a guide camera through a couple years of deep sky imaging. It was simple, reliable, and reasonably priced. When this latest crop of cameras got released I was ripe for an upgrade, so I started sorting through what would work best for me. First on the market was the ASI174MM (mono) and ASI174MC (color). Honestly, I was floored by some of the shots of Saturn I was seeing out of the Planetary Imaging forum. Next came the ASI224MC. It was a one shot color that was rivaling the ASI174MM due to extraordinarily low read noise. Both these cameras were providing capable users with astounding results.
But, back to reality. What could I expect out of my modest equipment? Let’s be honest, I wasn’t shooting out of a C14 under stable skies. And, I also want to shoot deep sky (currently I do that with an uncooled DSLR). I’ve long shopped for a CCD, but it’s hard for me to justify considering how much time I currently get for imaging. Plus, I somewhat prefer the jack-of-all-trades idea even if there are compromises. Being able to use a couple hours of clear sky for planetary without a massive equipment changeover is a pretty big plus. Cooled CMOS sensors are relative newcomers to the amateur astronomy scene and somewhat unproven. But I was willing to give it a go, especially with a camera I know, at the very least, is a top league planetary imager.
Those who have seen my images over the last few months probably know I shoot at a long focal length and I like galaxies, particularly ones that are less commonly imaged. For me, the decision on which camera to choose was not an easy one. A lot of what you see around for DSO CMOS images are shot with the lucky imaging mindset. Stack thousands frames to reduce noise. With low read noise, this can produce great result when targets are bright. My goal was, though, to see if I could go deep and pull out faint objects. I wanted to use it like a CCD. So, for that I ended up with an ASI174MM. It is the only mono version of the lot with a “larger” sensor and pixel size and more well capacity. A key compromise with any of these sensors is that they are indeed small relative to the APS-C that I was used to.
Digging around, I found a few folks already trying DSO imaging with these uncooled cameras. I wasn’t too happy with what I found. This chip architecture seems to have some nasty amp glow. I talked to Sam at ZWO about this and he was able to supply some sample lights and darks that show it calibrating out. I gotta say, I was a bit skeptical about the quality down in that corner of the frame. I was nervous that the thermal noise would be a problem. We shall see…
Edited by Thirteen, 22 November 2015 - 04:46 PM.