Birding Optics

How to Choose Binoculars for Bird Watching

Having a good pair of binoculars is important to anyone seriously interested in observing birds.  Birds are small, and quick to fly away, so if you want to get a good look, you need binoculars that will allow you to get a quick, clear, and bright view of the bird.

What the numbers mean: Binoculars are sold with numerical descriptions, like 7 x 35.  The first number tells how many times the image is magnified.  The second number is the diameter of the objective lens (the larger lens on the end of the binoculars), in millimeters.  The larger the lens - the more light the binoculars gather and the better you can see in low light conditions.

 For birding, buy binoculars with magnification in the 7x to 10x range.  Note that the higher the magnification, the harder is to hold the image steady in your hands.  As a rule of thumb for birding binoculars, divide the second number by the first number, if the dividend is 5 or greater, the binoculars will be suitable for birding.

Example:  7 x 35 binoculars.  35 divided by 7 = 5, therefore 7 x 35 binoculars will work well for bird watching.

Focus Systems:  Chose binoculars with a fast-focus system with a center focusing wheel that goes from infinity to near focus in one revolution.  Extra close focus is a nice feature for spotting perching birds. 

Lenses:  Look for multi-coated lenses, which improve light transmission noticeably.

For Eye Glasses Wearer:  If you wear glasses, buy binoculars that have roll down or retractable rubber eye cups.  This will improve viewing.