| 22-mm | |
| Model # | EN4-22.0 |
| Focal Length (mm) | 22 |
| Barrel Size (in.) | 2" |
| Apparent Field (deg.) | 82 |
| Eye Relief (mm) | 19 |
| Weight (lb / oz) | 1.50 / 24.0 |
| Field Stop (mm) | 31.1 |
| Compare to similar focal lengths | |
Applying the experience of the Radian development to the 82° Nagler series, yielded more contrast, reduced pincushion, more true field, and longer eye-relief. With added eye-relief, the click-stop Instadjust eyeguard helps maintain proper eye distance and centration.
For deep sky viewing, the comfort, clarity and contrast gets us closer to our "spacewalk" viewing goal.
To achieve various features requires different design tradeoffs and thus the different types of Nagler eyepieces. The largest possible true fields of view for an 82°' apparent field of view in both 2" and 1¼" formats are achieved with the Nagler Type 5 series, with focal lengths of 31 and 16 mm
Compact size in medium to short focal lengths is achieved with the Nagler Type 6, available in focal lengths of 13, 11, 9, 7, 5, and 3.5 mm.
To achieve eyeglass friendly eye relief without excessively large and heavy designs requires the other two Nagler types. The 22mm Type 4 and 19, 14, 9, 5.5 mm Type 7 with their long eye relief feature adjustable height eyeguards and are best for eyeglass wearers or Dioptrx™ users.
