Description
Tele Vue 31.0mm Nagler
Designed by Al Nagler and sporting his name, the Nagler eyepiece design came about as an effort to produce a sharp, high contrast wide angle "spacewalk" 82deg AFOV(apparent Field Of View) viewing experience through a telescope.
To achieve the full magnification range over 82deg apparent field of view requires two types: Nagler Type-5 with focal lengths of 31, 16mm and Nagler Type-6 with focal lengths of 13, 11, 9, 7, 5, 3.5, 2.5mm.
The Type-5 permits the largest true field possible (31mm has 42mm field stop).
Type-6 models have shorter focal lengths, are parfocal, with similiar size and weight, and all with a comfortable 12mm eye relief.
The Type-4 models feature about 18mm of eye relief and with the "instajust" eyeguard are best for eyeglass wearers or Dioptrx users in their 22, 17, 12mm focal length range.
Note: some Nagler models have been retired.
Specs
| SKU: | TVU-EN5-31.0 | 
| Model: | Nagler | 
| Coatings: | Proprietary | 
| FocalLength: | 31 | 
| EyeRelief: | 19 | 
| FieldStop: | 42 | 
| AFOV: | 82 | 
| Blackend Edges: | Y | 
| Keyed Barrel: | Y | 
| Barrel Diameter(in): | 2 | 
| Weight(lbs/g): | 2.2/998 | 
| Parfocal Series: | N | 
| Additional: | Dioptrx, FoneMate | 
 
             
             
             
             
             
            