Detailed Product Description
1609 L15X70 L-Series Binoculars:
CODE: 1609
Model:L15×70
Power: 15x
Objective Diameter (mm):70
Field of View ft@1000 yds/m@1000m:183/61
Height × Width(mm):260x230
Weight (g):1310
Other Feature: Long Eye Relief, Big eyepiece
Feature of L-Series Binoculars:
- Long Eye Relief
- Blue, Ruby, Green or Multi-coated
- Premium Image
- Fast Roll Down Eyecup
- Bak4 Prism
Long eye relief binoculars are specially designed for eyeglass wearers.
Optics within the long eye relief system direct the focal point further behind the eyepiece so eyeglass or sunglass wearers can see the full field of view wearing the glass.
Advantage of Bak4 optical glass
High-index Bak4 optical prism glass is better than the usually used low-index Bk7 glass.
The low cost glass Bk7 usually causes excessive refraction of light and trends to produce a vegnetting effect which looks as a rhombus shape around the edges of the image.
To compare this effect, just hold the tow binoculars in front of you at arms length, viewing through the eyepieces. In the binoculars with Bk7 prisms, you will see decreased will see decreased light transmission and image brightness compared with the clear crisp images of the binoculars with Bak4 optical glass.
