Calculated telescope focal length divided by manufacturer's reported eyepiece focal length. It gave the impression of being off-center. This is the eyepiece that came with the telescope. This will be addressed in a future update. Ultima 5-mm eyepiece field stop is small and close to the field lens.
Value given is a a ballpark estimate.
Construction quality does not match that of the Ultima 12.5-mm at all. Copyright 2000-2001 by Pietro Carboni. All Rights Reserved.