Two symmetrical lenses telescopically positioned on either side in such a way that they points in the exact same direction: that is the canon definition of binocular. Such a placement of lenses allows the viewer to observe or inspect a certain object using both eyes at the same time. Binoculars are relatively compact in size since they are ideally meant to fit in one's hands easily. Although most binoculars come in a size as small as that of opera glasses, there are certain military models as well which have exceptionally large lenses and tend to have a more colossal design. Unlike a monocular telescope, a binocular provides the viewer with a more depth sensitive perception of the image due to a three dimensional focus.
Choosing your binoculars
Size specifications and types
Depending on the kind of usage one may have, a binocular comes in various types and designs.
The full sized binoculars have a general size specification between 8*42 (length) and 10*50 (width). These capture more light and provide a wide and steadfast view. Such binoculars are ideal for wildlife viewing and exploration. They would however not be ideal for regular backpacking or camping purposes.
The medium sized binoculars have a size specification of 7*35 (length) and 10*32 (width). The transmission of light is not as powerful as the one provided by the larger lenses, but it is above average. Such a design and viewing capability is best for sport events and for some aspects related to wildlife viewing such as bird watching. They are cumbersome if taken on a camping or road trip.
Compact sized binoculars are best for backpacking purposes and for long durations related to travel and general sightseeing. The most common size specification for the small sized binoculars are 8*25 (length) and 10*25 (width).
Most binoculars are durable due to the magnesium frames which are light and easy to handle in terms of weight and size. In addition to this, the frames are surrounded with tight rubber grips that ensure easy usage in all weather conditions, and enable the user to hold the optical device with a better grip. Binoculars also generally come with a harness which can be removed or attached as per the requirement – something you might want to look for, depending on your needs. The leather straps attached to the device can be strapped on one's shoulder or neck. Generally those who prefer bird watching would want to consider a 10*40 binocular, or a 10*42 for viewing longer distances. Water-proof binoculars are also available which keep the lens from fogging up during harsh weather conditions. Moreover, these optical devices come with armouring which protect the lenses and keep them from getting scratched.
Field of view and eye relief
This is the side to side measurement of the circular viewing of the defined area or subject. A binocular with a wide angled lens offers a greater width in terms of visibility, and is better when it comes to focusing on a series of events. But the first thing that one needs to determine is the magnification power required. If the magnification power of a binocular is high, then the field of view tends to be low, and therefore a user needs to decide what weighs more importance before buying the apt binocular. The eye-piece design is also important when it comes to narrowing down on specifics since a wide angle design provides a better visual quality. Eye relief is the space between the two eye pieces and the viewer's eyes. A long eye relief in binoculars provides better comfort to the users and allows them to hold the binocular away from their face while maintaining a steady view. This is useful especially for those who wear glasses. The regular eye relief distance is 11 mm or more.
A binocular’s zoom capability is determined by the type, number, and disposition of lenses used in its composition, and varies greatly with type and intended use. The magnification can be altered with a lever or button generally provided on the device – a useful feature depending on your needs and one to be aware of. This allows one to zoom in further and get better picture clarity, or zoom out to get a wider perspective of the image. There are 2 aspects that go into defining a binocular. One is the intensification power, and the other is the width of the lens. A basic binocular model has a magnification power of 7, which means that if the user is viewing a certain object, it would appear 7 times closer than it would to the bare eye. There are some models that come with a magnification power as high as 10; however, steady viewing tends to be difficult since such models are hard to hold on to without faltering in movement.
Which binocular for which use?
The two important factors that need to be narrowed down on before investing in a binocular are the type of usage or purpose and budget. Those uses are generally listed by the sellers along with any particular feature present in the model; so the next step to ensure a good acquisition is that you find a respected and renowned manufacturer to attest for the quality of the product you are buying. Buying a binocular online is the best way to go about it since the specifications are listed according to one's requirement, and it is a one stop shop way of getting the best deal available.