The Keys to Choosing Binoculars

What to consider when selecting the best pair. The system explained in depth.

Activities outdoors, be able to see further and better takes on great importance, either to enjoy observing nature or – as in the hunting – properly evaluate our prey.

According to campingship, a binocular is a refractor optical system, in which the light enters through the objectives and is refracted towards the eyepiece lenses, passes previously through a system of prisms which makes the total length of the device is relatively short. The function of the prisms is increase the distance that light, thus preventing binocular is very long, as it would be if the light refractara directly between the objectives of input and eye lenses. Due to this system, it is called them also binoculars.

They are two types of design of prisms used in the construction of the binoculars: the Roof and Porro, the latter invented by Italian Ignazio Porro in 1854.

Using the Roof Prism Binoculars are compact and are characterized by their straight tube (see diagram).

There are several parts to identify in a binocular, which we can distinguish the objectives, or the front lens where light enters and whose diameter is measured in millimeters and is recorded in its name (30, 40, 50, etc.); eyepieces, which are light-emitting lenses and those that will come closer to our eyes (one of them, usually the right, referred to as “ocular focus”, whose proper use will see later); and the focus wheel, which is used to focus the entire optical system and see the scene or object with sharp – precisely.


A binocular increases are expressed to be followed by the letter “x”, which means the magnification factor. For example, “10 x” indicates the object that we can see will see it as if it were 10 times closer.

The target measured in millimetres diameter together with the magnification factor, require us to feature our binocular. Thus we have a 8 × 40 will allow us to see things eight times closer and that the entry of light is through a 40 mm lens. More diameter should capture of light.