Binoculars are the basic tool of birding. You need to be comfortable using them, so that finding a bird with them is second nature to you. Here are some tips to help you quickly develop your expertise with binoculars.
The first thing to do with a new pair of binoculars is to customize them to fit your eyes.
top-quality roof prism binoculars have eyecups that neatly slide
in and out, or they have twist up eyecups, letting the user
dial exactly the needed amount of eyecup extension. Twist-ups
also maintain their position without collapsing at crucial moments.
Most binoculars have folding eyecups. If you wear glasses, you should fold the eyecups down, like this. If you don’t wear glasses, make sure the eyecups are extended, like that.
Next, you want to set the interpupillary distance. Everybody’s eyes are different. Some are spaced far apart; others are closer together. So all binoculars let you adjust their two eyepieces to match the distance between your eyes.
Hold binocs up to your eyes and move the barrels closer together or farther apart until the two images become one circle.
It should look like this.
Then you should set the diopter adjustment to match your eyes. Many people’s left and right eyes differ in their vision.