Getting started with the right Binoculars

By Kelly and Brian Delaney, For the Birds Nature Shop, Mahone Bay, NS

We think binoculars are a lot like shoes – what fits one person may not fit another. You may choose a binocular based on something your friend has or a brand that you are familiar with and that may be not actually be the best fit for you. We find most people choose a pair for their optical quality, the focusing mechanism and the way the binoculars feel in your hand – and this can be different for different people. It also helps to understand some of the basics that will help you make the right choice based on what works best for you.

What do the numbers mean?

Binoculars are manufactured and sold as 8x42, 10x42, 8x21, etc. The first number is the binocular’s magnification – so an 8 magnification will make an object appear 8 times closer than with the naked eye. The second number is the size of the binocular’s objective lens (the one facing away from you) in millimeters. This means that a 42 is a larger binocular than a 21. The most popular combination for bird watching is 8x42.

So is a 10 magnification better than an 8?

Not necessarily. A stronger magnification may bring the object a little closer but you may lose image quality due to less light gathering or an unsteady hand. Stronger magnification diminishes the brightness of your image and it can make it harder to see field marks or small colour differences. If you are not steady when holding a stronger magnification, you will notice the image will vibrate or shake which also makes it harder to see the details.  When comparing binoculars with the same size objective lenses, higher magnifications will have a narrower field of view. Another reason so many birders prefer an 8 magnification.

Can I wear my eyeglasses with binoculars?

Ideally, yes. By the time you remove your glasses and bring up your binoculars, you can miss a lot of the action.  If you wear eyeglasses or need to look through your binoculars for long periods at a time you should choose a binocular offering at least 15mm in eye relief and with twist down eyecups. Eye relief refers to the distance (measured in millimeters) between the ocular lens (the one you look through) and where the image comes to focus (inside the binocular) and the entire field of view can be viewed. Most eyeglass wearers find the best view with the eyecups twisted down tight with the binocular and holding the binocular so it just touches their eyeglass lenses. If you wear multi-focal or progressive lenses, you’ll want to hold the binoculars so you are looking through the distance part of your eyeglass lenses.

I have trouble finding the bird when I look through my binoculars – is there a trick to it?

The trick is to keep your eyes on the bird and bring your binoculars up to your eyes. If you look down at your binoculars and bring your eyes and binoculars up together you will have more difficulty. The field of view of the binoculars can also make a big difference. The field of view is the distance from left to right that you can see when looking through your binoculars. This is measured either in linear feet at a distance of 1000 yards or in angular degrees. (One degree equals 52.5 feet). The wider the field of view, the easier it will be to find your bird and to follow moving birds.  A minimum of 300 feet at a 1,000 yards is recommended.

How much should I spend on binoculars?

Most experts agree that you should spend as much as you can afford – that you do get what you pay for. This is mostly true. Light transmission will be higher through more expensive optics than through modestly priced optics due to better optical designs, glass quality, and improved optical coatings. Better light transmission results in better image quality particularly at dusk and dawn when the birds are most active. The more you plan to use your binoculars the happier you will be that you chose the best you could afford.