I think everyone's journey is different. I can say that for me I did exactly the journey that you are talking about. I got a hyperstar-capable Celestron 8" (though not the edgeHD). I started with planetary imaging then went to DSO. I am no expert, but have been pretty happy with my results 6 months in (link to my astrobin). I decided against using Hyperstar, but that is a different thread/discussion.
That said, there were many, many challenges along the way that I spent way, way, more time (and $$) solving than I had expected to do I don't regret for a second going this path, but I think "eyes wide open" is important.
Couple things to go through:
Learning on planetary: Processing and tracking are completely different than DSO. Planetary you do not use a guide scope, you track using software like FireCapture that looks at the image and nudges the mount to keep it in frame. Also processing for planetary is all about "lucky imaging" where you take 100fps and then filter for the best then stack and sharpen. That all said, there is a lot to learn that translates. ASCOM, cameras, mount stuff, patience, frustration, etc.
Target size: Personally with the focal reducer I love the FL that I am at. I love the targets and the framing that I get. It is true I can't do wide field, but for me (personal taste) I am more excited about the smaller targets than the larger targets. You can go to telescopius.com and enter some telescopes and sensors and do searches for the types of targets you would see based on options. Then you can search astrobin for those targets to see good examples of them. You definitely should understand the different types of targets just so you are not surprised by what you can (and can't) do with the gear you get. Here is a link to my Astrobin with planetary and DSO targets on my 8" (link).
Scope size (8" for planetary?): Planetary imaging is mostly limited by seeing (e.g. where you live and the atmosphere). An 11" won't make your seeing better. That said, absolutely it is true that a larger aperture for planetary if seeing is good will produce better results. That said, here is a great thread from the planetary forum on 8" results (link):
EdgeHD: For me, the flatness of the edge is pretty subtle and not something I personally am concerned about (personal opinion). Here is a thread showing an example of the coma that you can see with non EdgeHD frames (link).
In summary, if you are the kind of person that can dig into technical details and be patient and sift through challenging diagnostic situations, AND if you like the targets you can see with the 1200 - 2200 FL scopes, by all means this is a great path. However if you like wider field targets OR if you are not super technical or patient, then SCT to start could be a recipe for giving up.
Either way, this is a great community of people here who can help when you get stuck. I am 100% sure that without CN and a couple other forums I would have given up by now for sure.
Edited by ryanha, 28 November 2020 - 03:51 PM.