_w195px.png)
|
Nagler
82° Apparent Field Eyepieces
|
TeleVue.com: Eyepieces > Nagler > EP_EN5-20.0 |
| 20-mm | |
| Model # | EN5-20.0 |
| Focal Length (mm) | 20 |
| Barrel Size (in.) | 2" |
| Apparent Field of View (deg.) | 82 |
| Eye Relief (mm) | 12 |
| Weight (lb / oz) | 1.04 / 16.6 |
| Field Stop (mm) | 27.4 |
| Compare to similar focal lengths | |
The 20mm Type 5 is a compact 1-pound, 2" eyepiece that fills out the eyepiece line and is a worthy successor to the heaviest commercial eyepiece ever produced: the Nagler 20mm Type 2, which weighed-in at 2.3-lb. when introduced in 1986.
To achieve the full magnification range over 82° 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 long eye relief and with the "instajust" eyeguard are best for eyeglass wearers or Dioptrx users.
