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How Binocular Magnification Works

How Binocular Magnification Works

If you’re considering buying a new pair of binoculars, it’s helpful to know how binocular magnification works. Otherwise, you might not get the product you need because you’re not sure what it is that you’re looking for. It’s best if you take the time to learn just a little bit about what the numbers mean so that you can buy the set that you’re happy with for your intended purposes. Fortunately, it’s all quite easy to learn, and it only requires a few minutes of your time to understand what you should be looking for in a product, and what you should avoid.

How Binocular Magnification Works

The First Number

The first number in the product name denotes the magnification strength. Whatever that number is, the object you’re looking at will appear to be that many times closer whenever you look through the lens. In other words, if the first number is 10, the object you’re looking at will appear to be 10 times closer to you when you look at it. If the number is seven, the object will appear to be seven times closer, and so on and so forth. There is a wide range of numbers, so it’s important to carefully consider the one that is a good fit for you before you purchase a set for yourself.

How Binocular Magnification Works

The Second Number

Most people think the second number is a little more confusing, but it’s actually quite simple to understand. It represents the size of the lens in millimeters. This is measured across the lens, not from top to bottom. Why is this important? It determines how much light is allowed through the lens, thereby making the object you’re looking at appear to be lighter or darker. The larger the number, the more light is allowed through the lens.

For instance, if the second number is 50, more light is allowed through the lens than if the second number is 32. It’s like looking at a photograph. Depending on the lighting when a picture is taken, as well as how the flash on the camera operates, an image can appear much lighter or darker than it really is versus looking the same as when you’re looking through the lens.

Many people use slightly larger numbers in order to make the object they’re looking at appear lighter, thereby making it easier to see and point out certain details. While this can be extremely beneficial, it’s important that you don’t go overboard when it comes to choosing numbers that are too large.  You will see why this is important in the following paragraphs.

How Binocular Magnification Works

What the Numbers Mean

The numbers are important. This is worth repeating here because it can make this subject a little easier to understand. This is important if you don’t have any previous experience with choosing the right lens numbers. To reiterate, the larger the first number is, the more magnification you can expect. The larger the second number, the more light there is coming through the lens, so the object appears lighter when you look at it. As is the case with most things, there is a happy medium here. Just because it seems like larger numbers make things easier to handle, that doesn’t mean that you should go for the largest possible numbers you can find.

How Binocular Magnification Works

More Isn’t Always Better

One of the problems you’re likely to encounter if you buy a set with a large first number is that the image can appear shaky. In fact, you’re really pushing the envelope if that first number is 12 and you’re planning on holding the binoculars with your hands. With a magnification of twelve times, you will need to hold the binoculars very steady in order to keep the object that you’re looking at still. At this point, you really should consider using a tripod. As long as you remember that with increased clarity comes a decrease in stabilization, you should be okay.

Generally speaking, it’s a good idea to choose values somewhere in the neighborhood of 7 for the first number and about 12 for the second. This would allow you to view most things with some decent clarity and still see some of the smaller details without giving up the stability of the image or making it appear so light that you can’t hardly see it at all in bright light.

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