Quote:
Originally Posted by SkyWatch
The maximum field stop for a 1 1/4" (32mm) eyepiece is around 27mm- and this dictates the maximum possible FOV - and therefore the maximum AFOV as well.
Televue note that their 32mm Plossl with a 50 degree AFOV and a 27mm field stop gives the maximum true FOV possible for a 1 1/4" (32mm) diameter eyepiece.
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A 27mm field stop in a 1.25" barrel would need to be very close to the front end of the barrel in order to avoid vignetting in a normal Newtonian scope.
So, even Televue are pushing it a bit because the field stop of their 32mm Plossl appears to be quite a bit back from the front end of the barrel.