Soligor Ploessl 6mm
Not really sharp image quality, poor towards the edge.
x-axis: distance from optical axis in °, y-axis: resolution in arc minutes
Apparent Field of View:
The apparent field of view is as big as 58°, but edges are only visible by turning the head (see eye relief).
Astonishing good, especially for this focal length.
Slight cushion distortion.
Very short eye relief because of the short focal length. Also if you fold back the rubber eye cup you have to turn your head to have a look over the whole field of view.
Like the Skywatcher and TS Super Ploessls.
Very well – except the definite blur. But this makes it a not recommendable eyepiece.