Art. –Nr. TV-NAG-3-6
TeleVue Nagler Zoom 3-6mm
Perfect at 6 and 5mm, below 4mm the edges become slightly worse. The general decrease in sharpness to shorter focal lengths is due to the diffraction limit of the measurement equipment. Therefore the eyepices is perfect on the optical axis for each foacl length.
x-axis: distance from optical axis in °, y-axis: resolution in arc minutes
Apparent Field of View:
The apparent field of view is 50° as given by the manufacturer.
Astonishing good, despite that this is a zoom eyepiece. As well as an outstanding eyepiece with just one focal length.
Small cushion distortion towards the edges, more at 3mm than at 6mm.
10mm of eye relief are acceptable if you do not wear glasses. Very easy to look in.
A perfect zoom mechanics with fix-points at 3, 4, 5, and 6mm will make you think that your decision to buy this eyepiece was correct every night of observation.
Strongly recommended for small deep sky objects as well as for planetary observations.