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Choosing a Binocular

We tell you what to look for when buying a binocular, things such as aperture, coatings, field of view, and intended use.
- Nilesh Vayada, Galileo Telescope Makers

Selecting the right binocular is a matter of picking the best combination of features for your particular needs, including magnification, bulk and weight, brightness, field of view, optical quality, and cost.

Size : Binocular sizes are expressed with two numbers: 7x35, 10x50, etc. The first number is the magnification (or power), the second is the aperture, or diameter of the objective (front) lenses in millimeters. For example, 7x35 binoculars provide 7-times magnification and have 35mm objective lenses. For a given magnification, larger objective lenses yield a brighter image in dim light, but also result in a bulkier, heavier binocular.

Power :The higher the power, the "shakier" the image will be, because small hand movements get magnified. Therefore, its recommended a binocular of moderate 7x or 8x magnification unless you have a specific need for more power. Lower-power binoculars also usually offer a wider field of view, allowing you to take in more of a scene at one time.

What Will You Do With it?
Hiking If you hike or travel a lot, you’ll want a binocular that is compact and lightweight, perhaps even weatherproof. An 8x24 or 10x25 would be a good choice.

Birding The most popular models for bird watching are 8x40 and 8x42. They’re small and nimble, offer steady hand-held views, and have sufficient light grasp to provide bright, well-resolved images. If you plan to study birds at close range, look for a binocular with a near-focus distance of a few feet.

Astronomy For stargazing, light grasp is the most important factor. Choose a binocular with at least a 50mm aperture. A 7x50 model is easily hand-held and provides nice, wide-field views of starry swaths. The higher-power 10x50 is also popular, and in fact is preferable to the 7x50 where sky glow is a problem. A tripod is recommended for a steady view, however.

"Giant" binoculars of 70mm, 80mm, or 100mm aperture will reveal fainter deep-sky objects and more subtle detail. If you can afford the higher price (and a good tripod) and don’t mind the extra bulk, you’ll be rewarded nightly with incredible views.

Of course, other factors should play into your buying decision too, such as eye relief, optical coatings, and mechanical construction email us for more info.