I'll share my experience with a C9.25. I've owned one C8, two C9 and two C11 over the years. I currently own a C9 Edge and C11 standard.
I keep going back to the C9, I just like the size, fit and capability of the scope. I tend to ignore the hype about its design being special as that's not important to me.
In terms of C8 vs C9 here's my observation:
- C8 seems tiny by comparison to a C9, it is a really nice form factor for portability, I would consider it grab and go ready with my alt-az EzTouch mount (not everyone would)
- C8 performs well on DSO objects and does a nice job on planetary as well. Imaging or visual.
- My experience has been the C9 does show more on DSO and planetary objects but I never performed a side by side comparison of the two scopes
The cigar galaxy always seemed to look great in the C9
It performs really well on jupiter and other planets
Globulars look noticeably better
C9 starts to push mount load capacity, particularly for imaging. While you can get it to work well on CGEM/EQ6 level mounts for imaging (visual works fine) don't bother if its a windy night, not without having some wind block/shelter, then imaging with it is going to be a challenge. Imaging with the C9 on my AP1100GTO on the other hand - it doesn't blink even on a night with strong of wind gusts
Basically, a C9 performs better than a C8 to a level that's immediately noticeable but not jaw drawing. Its a level of improvement one would expect.
If you have a C9, don't look at planets and DSO through a C11 or you'll want to upgrade. That jump is jaw dropping in my opinon. Saturn imparticular is really breathtaking in a C11 and you can spot quite a few of its moons. As others regularly report here, this step up to a C11 is much more noticeable and I agree. With a binoviewer, I find it's a real treat view planetary nebula and the FOV plus light gathering helps reveal a much more detail and contrast in those small planetary nebula. Its quite noticeable the improvement over a C9. But that's just been my experience. Also, I would add that in terms of size of a C11 vs C9 it seems to me to be less of a big a step up in size, whereas C8 to C9 seems more noticeable.
As I do more imaging these days than visual the C9 gets more use than the C11 as a result.
But that's only because its focal length with reducer provides the scale that I prefer to image DSO's at.
And I can only use the mount for one purpose at a time - imaging or visual.
If I had a second mount that would handle the C11, while the C9 is out imaging, the C11 would get a lot more use.
But dealing with another setup would complicate things and require investing more money than I care to at this time (priorities right).
I hope someone finds my experience with a C9 helpful.
Thanks - John
Edited by John O'Grady, Today, 11:43 AM.