Nadir Astro:
andrea tasselli:
Nadir Astro:
I would suggest to get new 2600MM (mono), it will be a good replacement for your current QHY9: slightly larger sensor, much more sensitive and less noisy. For OSC you need to have really good dark skies and even then targets like narrowband are missed.
Whatever is the OP choice you definitely do NOT need really dark skies to use OSC cameras. At all. My skies are Bortle 6 mostly and I use an OSC camera quite well. The issue, if there is one, is the amount of clear skies nights you have, per month, which can be pretty low in my neck in the woods, never mind good ones. As for narrowband targets I don't even know what are they.
Andrea, that is a common illusion that OSC camera works better under cloudy skies. Sure, you'll get instant color image instead of maybe unfinished mono. But objects are there, they don't go anywhere.
You can always return and complete the image month/year after. In return mono image will always be way deeper and cleaner from noise.
As for narrowband, you need to try it once. I know many astrophotograpers who image ONLY narrowband, never broadband.
Frankly, my replay was to your statement that you need very dark sky to use OSCs. You don't. You might need a good light pollution filter but that is par for course even for mono. As for going back year after year to the same subject I am a specialist, as my images testify. Out of necessity rather than choice, given where I live. And by the same token you could do the same with an OSC camera, only it is way simpler to do that way. And I know, as I have been shooting LRGB for a very long long time. Frankly I always preferred shooting RGB-Ha-Hb-OIII rather than relaying on the LRGB gimmick, if I could afford to do so. Much cleaner processing and imagery, in my view.
The final assertion that there are narrowband targets simply isn't true. They are just subjects that emits mostly in restricted spectrum bands but they can be captured with a colour array just as well, it is just a a different aesthetic choice.