The Magnification of Binoculars

What are the numbers mean on a binocular? And what binocular magnification should I choose?

The first number listed in a binocular size is binocular magnification, which refers to power and the second is refer to the field of view.
Looking through an 8x gives you the impression that your distance to the object appears to be only one-eighth of the real distance, the 10x is the same. And like with many things in life with magnification it’s possible to have too much of a good thing, a lot of birders will think of the more power they have the better they’re gonna be able to see, but actually, as you increase the power of binocular so you can find that it makes this most trusted tool of birding a little bit more difficult to use. Let’s see why one important thing to understand about higher power binoculars is that with this added magnification, the binoculars' field of view will decrease. This means as we increase the power we won’t have the ability to see as much to our left and right through the binoculars, which can make it challenging to quickly find birds with your binoculars and then track them as they move about through the habitat. Increasing power will limit the field of view at the same time. 

For example: the zoom magnification of SA401 APO spotting scope

And the magnification relates to not only the field of view but also the stability.

It makes birding pretty difficult with binoculars while walking. That’s because the magnification in your binoculars not only magnifies the image that you’re seeing. It’s also picking up on any movement in your upper body or your hands and that degrades the quality of the image that’s reaching your eyes. 

So the most recommends magnifications for birder of a binocular are 8 power binoculars and 10 power because you’re going to have that ability to hold 8x or 10x power blocker steady. An increase of power likely means we’ll be working with a narrower field of view high-powered optics can also be more difficult to hold steady so you might not want to use anything stronger than a 10-power binocular when you’re birding.
Choosing the proper binoculars will fit you on the path to better birding.