Field of view (FOV)

Another set of technical detail which is imprinted on the binoculars, could be something like this: 372 ft. at 1000 yds, as can clearly be seen in the image.

This is the field of view, the width of the view at the particular distance. In this case 367 feet at 1000 yards.

This is the “real field of view“, as seen through the binoculars 1000 yards away from where the viewer stands, as opposed to the “apparent field of view“, where the viewer stands to see the same field of view, but then without the binoculars and, obviously, much closer. Usually only the “real field of view” is imprinted on the instrument. It could also be designated in meters or in degree. The angular view of 367 feet at 1000 yards is 7 degrees. (every 1 degree represents 52.5 feet).

Many people think that binoculars with small objective lenses like pocket binoculars will inevitably have a narrow FOV. This is not true, since field-of-view is determined not by aperture, but by magnification and the way the optics inside the eyepieces have been designed.
Example: The Swarovski Optiks Pocket Binocular (8x20B-P, Green) is a very small pocket binocular (dimensions: 3.98 x 1.5 x 2.3 inches) and has an aperture of only 20 mm and power of 8, but an excellent FOV of 345 feet @ 1,000 yards. Compare this to the FOV of 330 feet of the full-size NIKON 7294 Monarch ATB 8×42 Binocular, with 8×42 specifications.

The huge Barska X-trail 20×80 Binocular has a FOV of only 189 feet at 1000 yards. This not only proves that aperture (in this case 80 mm) plays no role at all in FOV, but also that high magnification (20x in this case) impairs FOV severely.

Finally, the Nikon Monarch ATB 8×42 (model 7294), 10×42 (model 7295) and 12×42 (model 7296) differ only in one aspect: magnification (8x, 10x and 12x). The 8×42 has a FOV of 330 feet, the 10×42 288 feet and the 12×42 262 feet, clearly showing that the higher the magnification, the narrower the FOV.

The FOV is handy in particular for children who still struggle to find and follow moving objects with a binocular, but it should not be the deciding factor for adults.

Finally, don’t be fooled by binoculars marketed as “extra wide field of view”, or “wide angle binoculars” if these have magnifications of 12 or even more. With magnification this high, a binocular cannot have a “wide angle”. A good example is the Rokinon 12×50 Wide Angle Binocular with Ruby Lens, which only has a FOV of 288 feet.

Some binoculars marketed as “wide angle” actually do have wide field of view, like the Brunton Echo 8×32 Wide Angle, boasting an exceptionally wide FOV of 492 feet at 1000 yards.

But how about this one: The Galileo G-525swa 5 X 25mm Super-wide Angle Binoculars has a FOV of 814 Ft @ 1000 Yards -truly “super wide”! However, this also comes at a cost: A magnification of only 5x. An excellent choice for children still struggling to find and follow an object. For a discussion of wide angle binoculars and reviews of binoculars from different price ranges, please go to “Best wide angle binoculars“.

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