A good set of binoculars is a must if you want to watch faraway things clearly. To ensure the better vision of distant objects, binoculars are the equipment that people count on to. Whether you have an expensive binocular or maybe you may have a cheaper one, but it does not matter how much you spend on buying your binocular. The thing that matters most is how much you know about the art of how to adjust binoculars.

If you do not have proper adjusting capabilities, you would find that the best binoculars have no advantage over the worst one. Properly setting the eyepieces of the binoculars and the distances in between has its own science and skills. By controlling the central focusing knob the image seen through the binocular can be adjusted. There are specific rules to turn your diopter knob, if it gets turned out of precondition then the binocular will not be operable anymore until the knob gets ordered to its previous adjustment.

Knowing the following few simple facts, you can easily adjust binoculars. In fact, most of the binoculars nowadays have some helpful features that will help you get the right adjustment. But fortunately, that is not difficult at all, here are the proper guidelines for you to follow to get the right knob positioning of your binocular.


Eyecup is connected to the eyepiece of the binocular, which is normally used for two reasons. One is to bring comfort around the eye and brows and the other one is for the ideal amount of eye relief. Folding down the eyecups will give you the best result if you wear glasses.

That means you should keep the eyecups as close to the ocular lens as you can. Folding up the eyecups will bring you the best result if you do not wear glasses. That means you should keep the eyecups protruded from the ocular lens. For twist style eyecups, rotate it as counter-clockwise in the direction to bring them out and away from the ocular lens.

Adjusting the eyecup helps you overcome the differences one might have in their eyes because regardless of those differences it is expected that the binocular will give its best vision to all its users alike. To get the perfect eyecup setting, start rotating the eyecup counterclockwise which makes the elevate from the body of the binocular. Then try to look at one targeted distant object through them, and adjust it to your comfort.

This feature aims to limit your peripheral vision so that you can focus better on the object before you. On the other hand, if you want a wider vision, you might wanna keep those eyecups retracted, since that’s what ensures it.


Normally the interpupillary distance, which is the distances between the pupils of human eyes, is 55-75mm. Firstly, hold the binocular with a normal viewing position and extend the barrels grasping firmly to its widest reach.

Then move them in such a way closer together until the barrels are aligned with your eye sockets and you see the images with a view of a single circular field. Remember this setting so you can easily adjust your binocular further. In some cases, you may need to readjust the setting so remembering that also will be helpful for further use.

You can also make use of the rubber cup around the eyepiece for comfort, if you wear glasses then you’ll find them especially helpful, you can roll them however you find useful. Then bring the binocular to your eye level while holding the barrel of it. Then, continue to bend the binoculars up and down until you find the right focus.

You’ll be able to tell because that is when the visual will unify into one circular image, and if you are still seeing double image then repeat the process since it needs readjustment to fit your face and eye coordination.


For using binoculars, you’ll find this setting to be quite important. Virtually you will find almost all binoculars having center focus available on the market. Firstly, place your index finger on it and move it over its knurly and serrated edges to turn it. Then make the best use of the central focus knob to adjust for your left eye. After that cover the left barrel with the lens cap or close your left eye or put your hand in front of your left eyepiece.

focus setting

Try to take advantage of these settings, when you have the center focus wheel placed on the perfect position, you’ll be able to receive a much clearer view. However, changing the center focus means you will have to redo the diopter focus accordingly.

Let’s take a wildlife observer, for example, they do not have any presumption about where they’re going to find the creature that will peak their attention. So they have to constantly change the focus and dioptric adjustment setting manually. Using the center focus wheel, you can change the setting to see things that are more distant or closer with a few turns.


Besides center focus, there usually is a separate diopter task of which is to compensate for the unequal vision of our eyes. The normal characteristic of our eyes is that the visionary power is different for each of the eyes. So now set your diopter adjustment at level zero.

Then adjust the diopter wheel until your right eye gets a clear and crisp view of the image. Most people do not even know that there is this feature in binocular, which helps them observe better.

This operation will require focusing both barrel’s focus point and that can be done with the binocular’s central focusing knob. To complete the operation first set the diopter to zero, or in some cases, the center.

Turn the ring to it, and then start by covering the lens of the barrel which is affected by the diopter adjustment setting. To do so, you can use the lens cap, or if you haven’t got any, simply duct tape it, or use other measures you find suitable.

Now look through the uncovered lens, choose an immovable object for the calibration process to be more accurate. And use the central focus knob to adjust its focus setting. Keep rotating it until you find the image to be best clear and sharp.

On another note, remember to keep both eyes open while looking through one lens, even when the other one is covered. Because squinting one eye affects the other eye’s focus and thus tampers with the eyesight and hinders the focusing process.

Once you have that one lens focused as you want, uncover the other one, and begin to customize the other one’s settings through the diopter adjustment. Cover the other lens first, then look at the same object from the same place and start to fine-tune it by rotating the diopter adjustment back and forth until you find the correct position.

But make sure that the central focus wheel stays at the same place, and not moved at all. When the image feels sharp enough you can stop focusing it. The remove the lens cap and look through both barrels this time. You should be able to see effortlessly clear this time.

Try to keep the settings this way, some advanced binoculars have a locking system on the dioptric adjustment, so the settings do not get altered in any unintentional way.


For obvious reasons, while you’re buying a binocular, go for at least 7×32 or 8×32, the numbers stand for the measurement of magnification and the diameter of the front lens in mm, consecutively. As the budget goes up, you’ll see that there are various options and added features on those binoculars to ensure the best image experience possible.

For bird watching in winter, people tend to rely on the models which are fog proof. Also, people who wear glasses need binoculars with adjustable eye caps, so that you can manipulate the distance between your eyes and the lense to be able to see a wide vision. You probably would like to make a mental note in this case that it isn’t very wise to share your binoculars with anyone.

Since everyone has different sort of eyesight that requires different settings, so to match theirs if they change your binoculars adjustment, you’ll have to do the calibration from scratch. 


You will find this fact most interesting that almost 90 percent of people who have binoculars, do not know how to adjust it properly. The reason could be that we don’t research and experiment enough, we do not try to know what each feature does and how to make the best advantage out of them.

Ironically, a cheap one can give better service than the expensive one if it is adjusted correctly. So by following the techniques above, it will increase your binocular’s ability to produce bright, sharp, aberration-free images of viewed objects and you’ll be able to enjoy awesome experiences with your binocular.

You can read more- How do Binoculars Work

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