I have a couple of thoughts but maybe your opinions differ. So, would be curious to hear your feedback...........
Completely agree... but my experience has been ZWO outshines them in other areas like drivers, accessories, etc. Maybe I just had a bad experience.
Other than a lack of the micro-lensing effect, the other features only seem to slightly favor the 294mm, not making it a big leap better than the 1600mm. Am I looking at this wrong?
Having worked with QHY over the past 2 years due to being the implementer of the native driver in NINA, providing feedback and reports, their rewrite of their SDK - the underpinnings of native and ASCOM drivers alike - has resulted in their driver quality coming a long way. In particular, they have added a lot of low-level hardening and error state recovery to the USB code paths in their SDK since February, which I have noticed paid off a lot. Since a lot of NINA users with QHY cameras come to me with issues, I've noticed this drop in complaints. So this is just my take on it from sitting in the software trenches and kinda being forced into the position of acting as an interface between vendor and user when it comes to this stuff.
As for IMX294/IMX492-chipped cameras versus the 4/3 format stalwart that is the ASI1600MM and its Panasonic chip, there are some additional considerations. First, Panasonic has discontinued its CMOS imaging sensor division and the production of the Panasonic MN34230 sensor that is used in these cameras has been discontinued for some time now, with ZWO, QHY, and other makers of astro cams with this chip drawing on remaining stock to produce cameras. So this mono IMX492 comes not a moment too soon as there now is a proper chip to carry the mono 4/3 torch.
Second, the IMX492 is Sony's 5th gen Exmor R design; while it's not 6th gen (stacked silicon) it is still fairly recent tech and thus has the improvements one would expect over the MN34230 sensor - a much higher QE due to the back-illuminated design and a dual conversion gain amplifier system that grants you extremely low read noise (1e-) at a high conversion gain. This HCG mode is pretty much a godsend to DSO astrophotography... all the DR without the noise consequences. The full well size takes a hit due to this, however it is a very tolerable one.
Edited by dghent, 19 September 2020 - 12:53 PM.