最方便的行星高质量变焦目镜，美国生产，现货供应。
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Nagler Zooms
Zoomable 50° Constant Apparent Field Eyepieces
| 4 - 2-mm | | Model # | ENZ-0204 | | Focal Length (mm) | 4 - 2 | | Barrel Size (in.) | 1¼" | | Apparent Field of View (deg.) | 50 | | Eye Relief (mm) | 10 | | Weight (lb / oz) | 0.36 / 5.7 | | Field Stop (mm) | 3.3 - 1.7 | [url=]Compare to similar focal lengths[/url] |
The 2-4mm Nagler Zoom is recommended for fast, high performance scopes of 800mm focal length or shorter, such as the Tele Vue-60. It has click-stops every half-mm.
Why Are There 3 Types of Naglers?
To achieve the full magnification range over 82° apparent field of view requires two types: Nagler Type-5 with focal lengths of[url=]31[/url],[url=]26[/url],[url=]20[/url],[url=]16mm[/url]and Nagler Type-6 with focal lengths of[url=]13[/url],[url=]11[/url],[url=]9[/url],[url=]7[/url],[url=]5[/url],[url=]3.5[/url],[url=]2.5mm[/url].
The Type-5 permits the largest true field possible (31mm has 42mm field stop), while the shorter focal length Type-6 models 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[url=]22[/url],[url=]17[/url],[url=]12mm[/url]focal length
| 6 - 3-mm | | Model # | ENZ-0306 | | Focal Length (mm) | 6 - 3 | | Barrel Size (in.) | 1¼" | | Apparent Field of View (deg.) | 50 | | Eye Relief (mm) | 10 | | Weight (lb / oz) | 0.33 / 5.3 | | Field Stop (mm) | 5.1 - 2.6 | [url=]Compare to similar focal lengths[/url] |
This model has click stops every mm.
Why Are There 3 Types of Naglers?
To achieve the full magnification range over 82° apparent field of view requires two types: Nagler Type-5 with focal lengths of[url=]31[/url],[url=]26[/url],[url=]20[/url],[url=]16mm[/url]and Nagler Type-6 with focal lengths of[url=]13[/url],[url=]11[/url],[url=]9[/url],[url=]7[/url],[url=]5[/url],[url=]3.5[/url],[url=]2.5mm[/url].
The Type-5 permits the largest true field possible (31mm has 42mm field stop), while the shorter focal length Type-6 models 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
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