Binoculars: a faithful companion for expeditions and more

When looking for your dream pair of binoculars, it's easy to get lost in the jungle of offers. Individual models differ in parameters, construction and materials used. The price range is also huge. Therefore, to answer the question which binoculars are the best, you first need to know your own expectations.

Which binoculars should I buy?

Theoretically, this question should be asked at the very end of a long discussion about optical parameters, the production process and an overview of models available on the market. However, at the beginning of the search for your dream model, it is worth defining a few basic requirements so that when browsing through the binoculars available for sale (a wide selection available on combat.pl: https://www.combat.pl/optyka/lornetki.html ) you know what to pay attention to.

It will be crucial to determine what the selected model will be used for. Whether it's observing the night sky, navigating an oil tanker through rough seas, observing nature, hunting or spying on a spy selling plans for North Korea's newest steam locomotive, you need the right tools. When hiking, lighter and smaller models will work better, but at sea and when observing the sky, high magnification will be important and the size will be of secondary importance.

It is also worth determining what additional things we may need. There are many designs available on the market with variable magnification, with a built-in compass or with the option of mounting on a specialized tripod. The most expensive, specialized models may have built-in laser rangefinders or display the current position using satellite navigation.

The universal feature of binoculars, regardless of the way they are made, should be the quality of optical elements, at least basic resistance to external conditions and the repeatable operation of all mechanisms.

What are binoculars?

Historically, a binocular or binocular is an optical device composed of two telescopes coupled in parallel. Thanks to its design, it allows binocular viewing of distant objects. Compared to a telescope or monocular, the image obtained is brighter and with higher resolution. The spacing of both telescopes also makes the object of observation seem more plastic, due to the stereoscopic effect (i.e. visual perception that allows us to better determine the dimensions, depth and distance from the viewed object.

How are binoculars constructed?

Each binocular is made of several basic components. These are glasses, lenses and prisms enclosed in a housing. Depending on the optical elements used, individual models differ in the parameters of what we see (magnification, depth of field, light transmission, contrast and color saturation).

The oldest is the so-called straight binoculars, also called Galileo's binoculars. It is a device in which the spacing of the lenses is adjusted to the spacing of the observer's eyes. The system of lenses and glasses used allows for relatively small magnifications. Popular theater binoculars have this construction.

When looking for the best binoculars, we will almost always choose a prismatic design. This solution is based on the assumption that the spacing of the lenses is larger than the spacing of the observer's eyes. Prisms placed in the body between the objectives and glasses are responsible for equalizing these parameters. This solution, apart from reducing the distance between the glasses, allows the image to be reversed. Thanks to this, more advanced optical systems can be used in the lenses, which will ensure better light transmission and greater magnification. Thanks to a special hinge in the central part of the body, prism binoculars can be perfectly adjusted to the user's eye spacing.

Less common periscope or scissor binoculars. These are specialized devices composed of two periscopes placed on a common base. They allow you to observe objects from behind terrain obstacles and are usually characterized by high magnification.

Porro prism or roof prism?

With the exception of specialized applications, most users choose prism binoculars. Depending on the design of the optical systems used, they can be divided into two groups.

Porro prism binoculars

It is a relatively simple design invented by the Italian artillery officer Ignatio Porro around 1850. The use of two prisms allows the image to be rotated in two planes using the phenomenon of completely internal reflection. The structure of Porro prisms simplifies the construction of the binoculars and facilitates collimation (justification) of the binoculars - that is, setting the optical axes of the lenses perfectly parallel. The shape of this type of optical systems causes the lenses to be moved sideways. Although this makes the binoculars slightly larger, this solution improves stereoscopic vision.

Porro primacy binoculars

Roof prism binoculars

The roof prisms are more complex than the work of Ignatio Porro. Their shape resembles the sloping roof of a building, hence their name. These are systems with a complex shape that causes the light ray to refract up to seven times. This construction requires very precise processing and the use of very good coatings to achieve high image parameters. Unfortunately, this often translates into a high price. What do we get in return? Binoculars with lenses and eyepieces arranged along common optical axes. Thanks to this, devices constructed in this way are smaller and more handy than those using Porro prisms. However, smaller dimensions often do not mean lower weight. More complicated optics weigh more.

Roof prism binoculars

How to read binocular parameters?

The two most important parameters of binoculars are magnification and lens diameter. Manufacturers usually describe individual models on their basis. Magnification means how close the image will be when viewed using optics. The most common range is four to ten times. Models with twelve or sixteen times magnification are less common.

For hiking and nature observation, 6x, 8x or 10x binoculars are best. They will allow you to obtain a clear and relatively wide field of observation. Additionally, at such magnifications, image shake will be minor. The situation is completely different when observing the sky or other objects at great distances. Binoculars intended for this purpose have a much larger magnification range, reaching 24x or 30x. However, such devices are usually very heavy and require mounting on special tripods for observations. Models with adjustable magnification are less common. They require the use of complex optical systems, which usually translates into weight and price.

Another important parameter is the diameter of the lens. It would seem that the larger the better, because then the image is brighter and of better quality. However, this is only part of the truth. Light transmission is influenced by the quality of all optical systems and coatings used. A model with good optics, despite worse catalog parameters, can provide the user with a much better observation of the target than binoculars with a nominally larger objective lens diameter and magnification. However, most professional night or marine binoculars will have a lens with a diameter of 50 to even 70 mm. For everyday use, models with lenses with a lens diameter of 30 to 42 mm will work well.

What to choose?

To sum up, choosing the perfect pair of binoculars is not easy. However, there are a few universal parameters that are worth taking into account. The most important thing is the quality of the optics and coatings used, it determines what we will actually see. The second issue is ergonomics. The binoculars should be comfortable to use and easy to carry. The magnification range and the diameter of the lens determine the future use of the binoculars... With such knowledge, it will be much easier for you to choose the right model of binoculars on combat.pl.

Text and photos: Jakub Link-Lenczowski