The combination of materials results in an unusually high image quality for this price and makes the lens a real all-rounder for visual and astrophotographic applications.
Focal ratio 1:7
Aperture 180mm
Focal length 1260mm
FCD100 Triplet Optics
Temperature compensated cell allows collimation of the lens via three side screws.
Good as a basis for the do-it-yourself construction of a high-quality refractor