Each pair of binoculars is made up of two barrels, which contain both contain an eyepiece with a prism inside and an objective lens at the end. If your binoculars have an interpupillary distance (IPD) scale, note the value after adjusting the barrels for future reference.
Keep an eye out for grit and dust, as this position is more exposed to the elements. Use the retracted position if you wear eyeglasses.
Be wary of fogging during cold weather when your eyecups are extended. If you don’t wear eyeglasses, use the extended position.
On most binoculars, the diopter adjustment is located on the right eyepiece. On others, the diopter adjustment is located on the left eyepiece.
Don’t adjust the diopter setting just yet.
Once you’re finished adjusting the diopter, test the lens with your other eye—the tree should still appear sharp. If not, repeat the process. Note the final diopter scale for future reference. Don’t adjust the center focus wheel while adjusting the diopter.
The final view through your binoculars should seem three-dimensional. If you feel a strain in your eyes, the binoculars might be out of alignment. Contact your manufacturer if adjustments don’t make a difference.
As you get better, practice on moving animals, such as squirrels, rabbits, and birds. When you lock your eyes onto a distant animal, take note of features or landmarks around them and use them as points of reference when you look through your binoculars.
Scan around any bird you spot for other birds in its company. Try looking back and forward along its flight path for the best odds.
Don’t scan the sky directly overhead—birds are more likely to disperse across a wide area. Focus on clouds to help birds become more obvious against the background.
