A Ramsden can be made to have the exact same FOV as a Plossl. Edge correction isn't much worse and when the Ramsden is used in a scope of long enough focal ratio, they are tack sharp to the very edge.
Another thing when making a Ramsden with similar FOV and edge correction as a Plossl, you have to space the two lenses quite far and then eye relief becomes near zero, a small fraction of the FL. While in a Plossl the lenses can be spaced much closer and the resulting aberations compensated for with the extra lenses in them. So the effective eye relief can be still as much as 0.75x FL without compromising edge performance notably.
But few folks use such really long focal ratio scopes any more. Here is a scope suitable for my 60mm Ramsden with 50 deg FOV, eye relief of 0.2x FL, tack sharp to the edge. A 55mm Plossl for size comparison is on the table as well.
Edited by triplemon, 03 February 2025 - 11:59 PM.