For the purposes you describe I would go for the C11, aperture rules - center of field views are the same as the Edge and looking through less glass. The off axis view can be well controlled with good eyepiece selection. If you were going to do much prime focus imaging, the Edge would be the better choice.
The off axis view cannot be controlled by good eyepiece selection. Only a corrective element of some kind will reduce the field curvature and coma inherent in a standard SCT. It's not that bad to me, but some people do not like it.
In my opinion, based on the comparisons I've made, it depends on what aberrations affect the observer the most. Eyepiece selection has a profound impact on image quality one sees. Don't forget that with the Edge, the camera is relying completely on the optical tube to flatten the FOV. Visual observation is an entirely different animal and observers shouldn't just assume that carries precisely the same way into the visual world. The observers own eyes and eyepiece selection can have a profound impact on ones perception of the image.
Heck, there's observers who swear they see field curvature in one eyepiece vs others and others will say just the opposite. Also, collimation on the Edge is extremely tight because of the critical distance the secondary resides from the corrector. I've looked through several samples of the Edge and I still can't figure out what all the hype is about when used "visually". Photographically I can understand, but visually, not quite. Even scope sample of all brands have variances, even if it's the exact same model.
Just to put this into perspective, I test various samples of cass's with Darren Thibodeau who's a contributor to my website. We observe with numerous samples which we check. Just the other night I ran into sample of a 10" ACF that shocked me. It stood up to premium scopes I've tested. The sample was so staggering good that I told my friend not to let it go. Not all samples test exactly the same if you guys want to be that nit-picky about it.
That's not neccesarily to imply that all ACF's are better. I'm merely trying to say that not all these scopes test exactly alike if you really want to get down to it. I'm not trying to be mean, but when people continually assume that Edge's are always better than normal SCT's, that to me is a red flag. It's just not that simple.
Prime example is the Takahashi FSQ106 EDX. For imaging it produces a flat field. With a 35 Panoptic visually, it does not produce perfect pinpoints out to the edge of field. Take an NP101 and it produces pinpoint images with a 35 Panoptic out to the edge because the telescope was designed to be used with Televue's own eyepieces.
These are complicated optical systems. You can't just assume that because an astrograph is flat field with a camera, that it automatically means it's going to carry over to eyepieces. Sorry to rain on the Edge parade, but I just can't agree with all these assumptions.
Edited by Daniel Mounsey, 25 July 2016 - 10:28 PM.