Skywatcher Ultra Wide Angle 15mm
Very good sharpness within 50° apparent field of view, but gets worse close to 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 approx. 62°.
Very good contrast.
Very slight cushion distortion.
Good quality with foldable rubber eye cup.
If you are satisfied with 50° usable field of view - fine eyepiece. The eyepiece is recommended for use with F/5 or slower optics.