Pentax XW 30mm
Very good sharpness over the whole field of view.
x-axis: distance from optical axis in °, y-axis: resolution in arc minutes
Apparent Field of View:
The measured apparent field of view is approx. 67°, close to the 70° given by Pentax.
Very good contrast.
Slight cushion distortion.
Very comfortable at 20mm eye relief.
That’s nothing we have to report on earnestly for Pentax eyepieces. Look e.g. at the perfect grip coated body, use of high quality materials etc. The cap at the eye lens is removable and releases a thread (43x0.75mm), which can be used for fixation of accessories.
A two-inch sized wide angle eyepiece as it should be. The eyepiece is especially great for fast systems. If telling you about “useful starting at F/5” for the TS-WA-32, which means about 2/3 of the field of view are fine, the Pentax is nearly perfect to the edge at this focal ratio.