[AnakChan (Sean)]

Hi folks,

Well ok, not entirely newbie as I have a CentralDS Astro A7S which has served me well for the past few years however I’,m considering “graduating” from it.

I have the following scopes which I intend to do astrophotography :-
1) Takahashi Mewlon 250CRS (2500mm/F10) - this has so far been my current scope with my cooled A7S
2) Pentax 125SDP (616mm/F4.9 - with reducer) - large image circle akin to the FSQ106 88mm image circle
3) Takahashi FSQ85ED (450mm/F5.3)

I’ve been thinking of getting a dedicated astro camera and am thinking of dipping my toes into monochrome as I think a OSC isn’t going to be massive difference/improvement over my Astro’s A7S. Please do correct me if my thinking is wrong.

Having said that I’ve been thinking of the QHY600M or the ASI6200M as they seem to have the pixel pitches suitable for the aforementioned scopes above. I could go for a smaller sensor for the 250CRS/FSQ85ED with their smaller image circles but would be nice to get a full frame for the 125SDP and that’s where I think the IMX455 sensor is suitable. For either the QHY or ZWO, I’m likely to pick up a filterwheel and seeing the large sensor size, I’m guessing I’d have to go with ~50mm sized filters. I’m estimating at minimum, a USD$7000 investment there for either brands incl the LRGB and NB filters. As it is a substantial investment, it naturally has made me re-think of whether to just go for the OSC version of the QHY600/ASI6200; as such the initial question in the former paragraph.

Am I right or wrong in thinking that a dedicated OSC is going to be similar to my current Astro A7S, and that if I want setup up to the next level I should consider monochrome? If so, then if the QHY600/ASI6200M package are deemed expensive, I should look into a smaller monochrome sensor within budget? With my range of scopes I do have a preference of a 3.5-4 micron pixel pitched sensor.

Any advice you’re able to offer is truly appreciated.