Why in the world did someone decide to call binoculars with adjustable magnification “zoom binoculars”? I’ll never know.
Rifle scopes, monoculars, and spotting scopes are known as variable models if they can change their magnification. Whatever mad man changed this for binocs has driven me crazy. So what are zoom binoculars?
Zoom binoculars are those that can zoom, quite obvious. By zoom I mean they can increase or decrease their magnification to a degree which is often outlined in the binocular’s specs.
If you ever saw specifications that read something like 10-22 x 50 mm, you know they are zoom field glasses. 10 is the lowest magnification they can go, and 22 is the highest, with 50 mm being the objective lens. It’s not much different than that of rifle or spotting scopes.
Zoom binoculars are versatile. The ability to increase their magnification gives them a giant leap in versatility. An increased magnification in a pinch is a godsend.
Imagine seeing something in a field. Maybe it’s a deer? Ooh is it moving? Or is that wind blowing? Is that deer just a tree limb? That Travis guy said 8 power would be enough. In this situation, a little increase in magnification quickly answers those questions.
The ability to increase and decrease is handy in sporting competitions as well. You zoom in on a player, and he goes to make a pass. You lose sight of the ball and zoom out to find it again. Then zoom back in and watch the game unfold.
Instead of having too much or too little you can have the best of both worlds.
What’s the Catch?
Well, there are quite a few catches with zoom binoculars. First off, they have to be big enough to utilize the highest magnification available. You may also find yourself using 10 power, and it has the weight of a 22 power optic.
Next, the price difference can be substantial. When comparing two high-quality models of zoom and fixed power binoculars, it’s a big difference. If you are going the zoom route, you definitely need to invest in good quality binoculars. Not only for clarity but also for durability.
Zoom binoculars have moving parts compared to fixed power ones. More moving parts mean more opportunities and chances to fail. Because binoculars are two separate telescopes, the zoom factor can become uncalibrated, leaving you with one eyepiece at 10x and the other at 15x.
Fixed Power Binocular
The classic non-zoom binocular has been around for quite some time and is still the bell of the ball.
Fixed power binoculars come in at one single power, and you are stuck with it. The power has a broad range from 4 power to 50 power. Anything high as 50 power is going to require a tripod, and at that point might as well be a spotting scope.
Well, they tend to be tougher and less failure prone. They are also smaller and lighter than zoom binocs in most cases. Let’s not forget they are much cheaper in general. Also, more companies produce fixed power than zoom field glasses.
One of the biggest advantages is their field of view. On average, it is double the FOV of zoom binoculars. This is due to the moving pieces inside the zoom eyepiece. It is an inherent design flaw that limits you significantly. A 50% loss of FOV is something you need to consider.
Of course, if you need that extra zoom and don’t have it you’ll also be up to an undesirable creek without a paddle. For some, the choice is easy. For others, I certainly see the merits of both zoom and fixed power binoculars.
Based on Purpose
I feel that the best way to choose a set of binoculars is how you plan to use them, and in what role they are to be used. So I’ve broken down its most common uses and the best option for it.
Hunting – Fixed power binoculars for sure. They need to be tough, rugged and ready to take a beating.
Tactical – Same reasons as above for hunting.
Long range nature observation – Zoom binoculars mounted to a tripod make it easier to see and enjoy nature, occasionally zooming in to get the finer details.
Sports – Zoom binoculars make it easier to focus on either whole game or specific areas of the match. A fixed power is going to give you one or the other.
Birding – Either. This is the hobby where both works well. I can certainly see an argument for either type of binocular here.
Regardless of what type you choose to use, make sure they are good quality binocs. Never settle for junk when it comes to optics. Think of them as an investment, not as an expense.