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Magazine > Practical tips > Tips and tricks > Adjusting binoculars
Practical tips

Adjusting binoculars

Are you seeing double? Don't panic! Your binoculars aren't broken, just not properly adjusted.

Fernglas Okulare Nah

Adjust your binoculars yourself in 10 minutes

Enjoying nature with binoculars is one of the most amazing experiences. A day spent viewing mountains and crevasses, admiring the plumage of our native birds, or immersing yourself in the fascinating world of astronomy. Often unforgettable moments are captured with binoculars.

It is therefore important to care for your binoculars and treat this optical instrument carefully, because your device consists of many optical components upon which your viewing pleasure depends.

When your binoculars no longer deliver

However, it can sometimes happen that your binoculars no longer demonstrate their usual optical quality. In extreme cases, you may not see one image, but two individual round images, that are visible separately. If this is case, your binoculars are out of alignment. This means that the optical components (especially the prisms) are no longer in alignment with one other. But don't panic! Your binoculars aren't broken, just not properly aligned. Maybe they were shaken roughly, or dropped.

If your binoculars have Porro prisms, you can easily realign them yourself with just a few basic tools, and be back to full viewing pleasure in no time.

Therefore, we would like to give you a brief guide to how you can realign your binoculars. Many Porro prism binoculars are aligned in a similar way.

1.

First, you should test whether they really need to be aligned. To do this, it's best to attach the binoculars to a tripod so that they can be held steady. Position the binoculars and tripod so that you can relax and observe the landscape from the comfort of a seat. If everything is clear, good and comfortable to view, no alignment is necessary for your eyes. If you see double images or even feel slightly dizzy, the binoculars are probably not correctly aligned.

2.

As you look through the binoculars, it is a good idea to point them at a house or building that conveniently has both vertical and horizontal straight lines. However, the object should be located some distance away.

Now, look through the binoculars alternately with the right eye and then with the left eye. If you quickly and alternately open and close your right and left eye, you can easily see any difference between the two visual impressions. If the binoculars are misaligned, it appears that the object is jumping back and forth. A vertical misalignment is always more problematic than a horizontal one. Height differences are difficult for the human eye to compensate. On the other hand, small horizontal differences can be quite normal and are not as problematic.

3.

If the binoculars are misaligned, you will probably see the horizontal wall edge bounce up and down as you switch from one eye to the other. If this is the case, you definitely need to take action. To align, we recommended that you work with two screwdrivers simultaneously. Position both screwdrivers in the adjusting screws and, at the same time, look through the binoculars. Now sensitivity is required. You only need very small movements of the screws in order to align the prisms.

4.

Besides a wall, a fir tree with its various branches can also be a good object to use, because the individual branches must be brought into alignment.

5.

If the wall edge in both images is horizontal or the branches of the tree line up, you have managed a sufficiently good alignment. The image should now be sharp and the view through the binoculars should give you pleasure once again. Quickly switch the view between your right and left eye again to check the alignment. If the image is comfortable for you, your alignment is completed.

In some individual cases, you may find that that your personal alignment does not seem entirely perfect to another person. But don't worry about that, because no human eye is exactly like another. Even small changes in a person's ocular alignment can lead to a completely different visual impression. Nevertheless, a compromise alignment can usually be found.

You don't want to deal with adjusting your binoculars on your own? No problem at all!

Send them to us at Astroshop. We can accurately adjust your binoculars according to your wishes.

Tip:

The small screws for adjusting the prisms are hidden under the rubber armouring. You can align them yourself using a small screwdriver. Clearly visible differences in height between the right and left image as seen through the binoculars. While continually changing the view from the left to the right eye, the binoculars should now be carefully aligned.