Orion 10 x 42 Waterproof Monocular

The magnification factor, also known as "power", is listed as the first number given in a binocular's name, like 7 x 50, 8 x 40, etc. In the first example, these binoculars magnify an image 7X more than if you were looking at that image with the "naked eye". When talking about zoom binoculars, the magnification is listed like this: 7-21 x 50. That means the binoculars have a zoom mechanism that takes the power from 7X to 21X as far as the eye can see. Please note that it doesn't matter whether there is spacing between the numbers or whether the "X" is upper- or lower-cased.

Don't always assume that more magnification is better! The more power, the harder it is to keep the image stable when hand-holding binoculars. Most people can comfortably hand-hold up to an 8X (most popular for birding), but after that, you may or may not need a tripod for a shake-free view...it depends on your own steadiness and how long you plan to view.

The aperture of a pair of binoculars (or any optical instrument) refers to the diameter of the main optics. Of course, binoculars have two main objectives that are the same size, but the number given for the aperture refers to just one. For instance, 8x50 binoculars have an aperture of 50 mm (and a magnification factor of 8), but unlike a telescope, they have two 50 mm objectives. The larger the aperture, the bigger the binoculars, but more importantly, a larger aperture draws in more light and lets you see more detail in shadow, shade, and other low light conditions.

Shopping for binoculars by body size is a great help if you already know you want a pair of compact (small) binoculars or you are looking for large aperture optics for astronomy. In general, the larger the body size the heavier the binoculars will be and the more likely you may need to mount them on a tripod when viewing for any length of time.

Close focus is pretty self-explanatory, it is the shortest distance you can be away from your subject and still focus your binoculars, however, why you might concern yourself with close focus isn't as obvious. If the only thing you'll be using your binoculars for is viewing at a distance, then you may not see the value in paying for extra-close focus. However, if you can think of any reason why you might want to have your body far away but view things up-close, it is well worth paying for. Bird-watching, bug & reptile observations at a safe distance, reading the small (or faded) print on signs, you get the idea!

While there are certainly individuals who don't require a pair of waterproof binoculars, we recommend it for most people. If you will be out on the water, at the beach, in snow, or find yourself in situations where heavy dew is present, you should consider the protection waterproofing can offer. If a pair of binoculars is waterproof, it can withstand getting caught in the rain, dropped in a puddle or getting a beer or soda bath at the ball park. Waterproofing can also keep fine dust and sand from entering the optical system.

Keep in mind that "water resistant" is not the same as "waterproof". Most binoculars that are water resistant can get a little wet as long as you dry them off as soon as possible, but they will not keep liquid out if submerged or kept wet.

Most binoculars, with the except of very small models, are designed to be attached to a tripod with an optional binocular tripod adapter. Using a tripod when observing for longer periods of time or at high magnification (or both) helps keeps the image shake-free. If this filter says "No", but you would like to use a tripod, there are a handful of adapters that wrap around the binoculars instead of threading into a 1/4-20 built-in port.