How To Get The Most From Your Binoculars
How to Get the Most
from Your Binoculars.
Binoculars aren’t as foolproof as a riflescope. Sometimes the picture doesn’t look like we expect, and the binocular isn’t always to blame.
I’m going to provide several tips to help set up your binocular to give you the clearest images, as well as choosing the right binoculars for your particular use.
Adjusting the Binocular Spacing
Improper spacing of the lenses can cause all kinds of discomfort while viewing.Most binoculars these days allow you to tune the distance between the two eyepieces, though some still don’t. The usual process is to fold the binocular or unfold it to adjust the spacing.
The general wisdom is to adjust the view until you are seeing a single circle. While it sounds simple enough, this isn’t always so easy because people’s eyes are different.
If you can’t seem to get a single circular view due to astigmatism or some other condition, just adjust close to it, and then tune your binocular until the viewing is comfortable for you.A few binoculars will allow you to lock this setting. If they do, then lock it down once you have it.
Setting the Diopter
Now it’s time for a little target practice. It’s best to do this during the day but it can also be done at night with a star, planet, street lamp, or distant light.One of the eyepieces on your binocular should have an adjustment ring for tuning the diopter setting.
You see, people’s eyes rarely focus the same. One eye might focus a little closer than the other. This diopter setting allows you to tune your binos to your eyes.
Close the eye that is in front of the adjustable eyepiece, and focus the binocular with the regular focus ring, which is typically in the center. Make certain that your target is as sharp as it can be.Now close your other eye and open the first. The eye in front of the diopter setting ring should be open. You will notice that the target is no longer sharp.
Leave the focus adjustment alone, and turn only the diopter ring until you have a sharp image.
Now open your eyes. You should have a clear view of your target, and whatever else you focus on.Many diopter rings can be locked with a set screw. If your binocular has this feature, then lock it down.
Don’t Let Other People Use Your Binoculars
Everyone’s eyes are different.
If you let someone else fiddle with your binos, you will have to reset it to your eyes the next time that you want to use it.It’s easy enough to do, but it can become a hassle if you are in the field and everyone is using the same pair of binoculars.
I used to attend a lot of star parties, where people gather with their telescopes to view the heavens and try out new gear.While nearly anyone was allowed to look through any telescope (with permission of the owner, of course), nobody there will let you touch their binoculars.
It Could be Your Binoculars
This happens when people try to get too much magnification through too small of an objective lens. It’s a little complicated, but it has to do with the size of your pupils, the light cones coming from the binocular (called the exit pupil), and some math. Here’s the simple version:
All binoculars have a number that follows the formula AxBB. A is the magnification, and BB is the size of the objective lenses in millimeters. A 7×50 binocular would be 7x magnification and 50mm lenses.
For daytime viewing, it doesn’t matter much. As the setting starts to darken with overcast, shade, or even viewing the sky at night, these numbers become more important.
For night viewing, the second number should be 6-8 times as much as the first. A 7×50 is a good choice for astronomy, as 50 is just a bit more than 7 times higher than the magnification of 7.For bird watching, hunting, or other daytime activities, you don’t need as big of a piece of glass, but it’s still good to have at least 3-4 times as much objective as the magnification, like an 8×32. This will ensure a brighter picture than smaller binos.
There are two causes of bouncing images that refuse to sit still.
The first and most obvious is too much magnification. Binoculars above 8x become hard to steady up, and above 10x they are pretty much useless unless you have them mounted to a tripod.
High power bino viewing is a skill.The other problem is fatigue, and it can happen if your binos are simply too heavy. Two pounds is about the maximum most people can use, and if you are viewing for a longer time, keeping the weight down will help you avoid both cramps and shaking hands.
Binoculars aren’t as simple as picking up a pair and gaining a magnification bonus.
By choosing a modest magnification for your activity and keeping the pair light, you can get much more enjoyment out of them, but the basics of knowing how to set them up to match your eyes is equally important.
Grab a pair, tune ‘em to your eyes, toss them in your hunting day pack, and go enjoy nature.Richard Douglas is a long time shooter, outdoor enthusiast and technologist. He is the founder and editor of Scopes Field, and a columnist at The National Interest, Cheaper Than Dirt, Daily Caller and other publications.