Is there an advantage to lower FOV? (1 Viewer)

I notice many of the Japanese made, and premium top notch binoculars still only have 50-56 afov.

My Vortex Vipers 10x42 have 61 afov, while some of the other newer binoculars push 65+ afov (340 feet+ for 10x, 430 feet+ for 8x.)

Is there an advantage to a lower FOV? like in the 50-56 afov range? Is the image better, less distortion, flatter?

In lower powered binoculars 6x and 7x binoculars typically have AFOVs (Apparent Field Of View) in the 50º-56º range while they also can have quite wide Angular FOVs of around 8º or 420'@1000 yards and even more. The image can be just as good and even better depending on their optics. The image will just be smaller than that seen in 8x and 10x binoculars.

There aren't very many 8x binoculars which have Angular or actual FOVs of 8º and more (The Nikon 8x30 EII is one) and with 10x binoculars with Angular FOVs of more than 7º (367'@1000 yards) are not common although they may have wide Apparent FOVs.


Nikon gives both the Angular FOV and the Apparent FOV in its binocular specs. Here are the specs for the new Monarch HG 10x42:

http://www.nikonsportoptics.com/en/....html#tab-ProductDetail-ProductTabs-TechSpecs

And here are the specs for the Nikon 7x42 EDG: Notice the difference in the Apparent FOV between the HG 10x42 and the EDG 7x42.

http://www.nikonsportoptics.com/en/....html#tab-ProductDetail-ProductTabs-TechSpecs

Here is Eagle Optics explanation of the two with an explanation of how to convert Angular degrees to linear feet.

https://www.eagleoptics.com/pages/field-of-view


Here is another good but technical discussion of it:

http://www.cloudynights.com/topic/1534-binoculars-apparent-fov-vs-true-fov/

See the second post there in.

I use 7x42 binoculars often enough so that I don't really pay attention to their smaller Apparent FOV. Mine range from 7.4º Angular to 8.6º Angular.

Bob

There are some (potential) advantages to a smaller AFOV:

• Eyepieces with a smaller AFOV are simpler to make and thus cheaper.
• They're also quite a bit lighter than eyepieces with a large AFOV.
• A large AFOV also requires the use of larger prisms, making the binoculars more expensive and, of course, once again heavier.
• Another aspect is that some parameters (freedom from glare, ghosts and unwanted reflections) are more easily controlled in binoculars with a smallish AFOV.

In other words: The larger the AFOV, the more difficult and expensive it is to achieve a high image quality, especially when the binoculars are also designed to be useable for eyeglass wearers. And binoculars with a large AFOV will also be heavier than ones with a smaller AFOV.

Hermann