Is an R/C (R/FF) worthwhile in a standard SCT for the field flattening and coma correction, regardless of the reduction in f number and potentially wider TFOV? If you are going to use Ethos or Ethos-SX or other 100 degree+ AFOV eyepieces in the SCT, won't the flatter field and coma correction be worth stacking the R/C into the system?
You don't even need to bump up against any potential vignetting problem due to the faster f number and the baffle-tube bottleneck. Just shift the focal lengths of the set of eyepieces you use to avoid vignetting. Is the R/C worthwhile for the flatter field and coma correction?
Actually, this is why I like my 8" EdgeHD with or without the 0.7x reducer. I enjoy the flat field and sharp image. My eyes no longer accommodate for focus. I appreciate any optics which deliver a flat field without my eyes having to do the work - because my eyes can no longer do the work! That's also why I like flat field eyepieces, flat field binoculars, and field flatteners in fast refractors.
To my eyes, the image in my 8" EdgeHD is very similar to the flat fields I enjoy in my Canon 10x42 IS and my NP101is. Yes, it's that good.
Edited by Sarkikos, 23 June 2022 - 08:16 PM.