An interesting development occurred in the online imaging world when Cloudynights recently changed the name of their "CCD imaging" subforum to include CMOS. It's now the "CCD/CMOS Astro Camera Imaging and Processing" subforum. At least 50% of the threads are about the newer ZWO ASI 1600 or the QHY 163 cameras. Some folks are entering the imaging scene with the "new" CMOS technology and a whole bunch of others are either making the switch from DSLR or adding a second "ccd" camera to their equipment list. These newer cameras have better QE than the last generation of CCD's -- specifically, they have a 30-50% higher QE than the recently popular KAF8300 cameras. Both the ASI 1600 and QHY 163 camera use the Panasonic MN34230ALJ CMOS sensor which is used in security and surveillance cameras. ATIK just entered the fray with their Horizon camera.
I haven't seen so much sustained interest in a specific sensor in awhile.
Besides the fact that the KAF8300 is getting really "old" as an amateur ccd choice, I think price is getting people in the door. The ASI 1600 is about half the price of a 8300-based camera. (It's much less if you consider the 8300 choices from FLI, Apogee, and SBIG's STT camera.) And there are now cheap filter choices from both ZWO and a company named Optolong. One consequence of all this is that there are many more new PixInsight neophytes posting on Cloudynights. There are regular discussions about workflows and processes which I find useful and interesting. In fact, some folks are routinely posting their exact workflows with their finished images.
Just a decade ago, monochrome imaging with filters used to be the domain of "serious" imagers. But one of the draws of monochrome sensors with filters is that you can shoot narrowband. H-alpha or Oxygen-III filters allow only a very narrow frequency range of light. And more importantly, these filters block all other frequencies of light which includes the light we see as light pollution. So, suburban backyard imagers are now able to shoot right through their city light pollution and capture nebulous objects. This is obviously a draw for most folks who live in or near large cities.
Of course like all new tech, these CMOS cameras have some drawbacks. While super sensitive, the sensors have amp noise which must be subtracted with darks. The nature of the darks and signal noise seem to vary from one chip to the next. Some people are having difficulty getting rid of the amp noise. Also, many of these CMOS chips have shallow wells. So, the stars saturate quickly and it can be tricky to go super long on your exposures. The preference is to do many short exposures (like 100 x 2 min.) which also changes the equipment requirements a bit. Finally, the size of the chips are somewhat restrictive. If you want to go color, there are full-frame and APS-C choices. But for mono, we're looking at APS-C and smaller.
I don't know if it's a sign of anything, but I've been looking for a used ASI1600 on Astromart and they are hard to come by. The ones that do appear usually sell within a day or two.
Just some observations as an alternative to the normal political noise that seems to permeate media these days...
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