Choosing a good pair of binoculars is not an easy task. The fact is that this observational device is quite complicated, not every factory will be able to produce a thing that meets high standards. In addition, depending on your needs, binoculars should have certain characteristics, and there are quite a few of them. What points should you pay attention to when choosing?
For what purpose
First of all, you need to decide on this issue. It is best to make a list of all situations where this device can be used. There are a lot of nuances, for example, a device only for daytime operation will be radically different from binoculars, through which you can see something at dusk or even at night. If you are constantly on your feet, it is better to take a lighter model, but bulky and not very comfortable binoculars will have excellent characteristics. Having decided on these questions, you can proceed to the technical parameters.
Galileo binoculars (theater) and field glasses
Theatrical binoculars give a direct image, but they have a very significant drawback: a small field of view. The magnification is also not very large, so these models are mostly used in stadiums or theaters. Field binoculars have several prisms that are needed to flip the resulting inverse image. This technology makes it possible to shorten the length of the device and significantly increase the visual field.
Types of prisms
There is a classification of binoculars according to the prisms used. The classic models use PORRO prisms. In this case, the eyepiece and lens are stepped rather than on the same straight line. In the case of ROOF prisms, the eyepiece and objective are aligned to make the construction simpler. Such binoculars will be much more compact, but the price will also be significantly higher.
The size. Full size binoculars
It is best to start the selection with the size. According to the standard classification, full-size binoculars are considered to be those with a lens larger than 40 mm. Such a device absorbs a large amount of light, which allows for perfect image quality even in bad weather conditions. A large lens also provides a larger field of view, which will make it possible to find the desired object faster. These binoculars are great for observing the sea and nature. The disadvantages include the weight and dimensions of the device.
Medium binoculars
Medium binoculars include devices with an objective range of 30-40 mm. In comparison with full-size models, it is much more compact and lighter, such a device will be easy to wear on the body for a long time. The image quality is slightly worse than that of large models, light is transmitted quite well. In most cases, it is used in sports competitions, as well as during active recreation in nature. Perfect for orienteering on the ground.
Compact models include devices with a small lens, as a rule, for such binoculars it is less than 30 mm. From the point of view of convenience, the small binoculars have no analogues; they can even be put in a pocket. However, the requirements for such an optical device cannot be very high. A clear picture can only be obtained in daylight. The field of view is small, which also creates certain inconveniences.
Magnification or multiplicity, lens diameter
One of the main indicators. On any model, the magnification is immediately after the name, after which another parameter is indicated: the diameter of the lenses. That is, the marking 7 X 35 means that this binoculars magnifies the object 7 times, and the size of the front lenses is 35 mm. 7x magnification allows you to view the subject as if it were 7 times closer to the observer. Some device models have a zoom, that is, the ability to change the magnification. However, these models are inferior in standard image quality. The size of the lens will directly affect how much light enters the device, and hence the brightness of the image. However, the larger the lens, the more massive the binoculars, here you need to find a middle ground.
Exit pupil
The exit pupil is also important for the performance of the device. This is the width of the beam of light that exits the eyepieces and reaches the observer's eyes. The parameter is calculated simply, you need to divide the diameter by the magnification of the binoculars. That is, if the body is marked 7 X 35, the exit pupil size will be 5 mm. There is a direct dependence of the image brightness on the exit pupil diameter. For normal purposes in daylight and twilight, it will be sufficient to choose binoculars with an exit pupil of 4 mm.
Angular and linear field of view
The field of view is a “piece” of space visible to the observer. The angular field of view is measured in degrees. Naturally, the larger this parameter, the larger the area can be seen. The linear field of view is measured in meters. This parameter means the maximum linear dimension that can be viewed at a distance of 1000 meters from the observer. In principle, these characteristics are the same, only they are measured in different quantities. This parameter is associated with the magnification, the larger it is, the higher the angle of view.
Relative brightness
Relative brightness is the amount of light that reaches the eyes through the lens. The higher the number, the clearer the image is. However, the brightness depends not only on the size of the lens, but also on the prism and optical coating used. For this reason, it makes sense to prefer products from elite manufacturers. Modern technology makes it possible to create small binoculars with high relative brightness.
Resolution limit
An important enough characteristic, talking about the minimum distance between two corner points, so that they do not merge with each other. This indicator indicates the ability of binoculars to distinguish the smallest details. In this case, the image will be sharp and clear depending on the value of the angle value. The lower this figure, the better, however, you need to make sure that the maximum resolution of the lens does not impair the resolution of the eyes.
Focusing system
Helps to adjust the device to the physical characteristics of your vision. Most binoculars are equipped with a diopter adjustment lever. With its help, you can get the clarity of the picture. Some models allow you to adjust the left and right side of the binoculars separately. This function is useful for those who have a significantly different visual ability of the eyes.
Relative brightness and twilight factor
The "skill" of binoculars to select light is called relative brightness. With the value of this parameter in the range of 1-16, the device can only be used for daytime observation. The indicator 16-25 makes it possible to use the device at dusk, and 25 in any conditions except complete darkness. The twilight factor is the quality of the resulting image in low light. Such parameters are taken into account only by elite manufacturers.
Night binoculars
These devices are allocated in a separate group using infrared radiation. In these devices, the operating time of the power supply is very important. Switching on in a bright light can damage the sensitive device, therefore the protection against accidental switching on of the binoculars' night mode should be located so as to exclude accidental operation. As a rule, these devices are among the most expensive binoculars.
Availability of additional functions
When choosing binoculars for tourism, hunting or fishing, it is advisable to purchase a fully waterproof model, which will allow it to be used in any conditions. A very useful function for hunters will be the built-in rangefinder, and for sea cruises it is advisable to choose a model equipped with a stabilizer. If the device will be used at extreme temperatures, a specialized model with a range of -50 ... + 50 ° C should be selected.
Manufacturer's choice
Modern technologies make it possible to make binoculars even in artisanal conditions, for which it is enough to cut plastic lenses and place them in a rubber case. Moreover, outwardly similar binoculars will not be inferior to professional ones. For this reason, it is only necessary to purchase a device designed for continuous use from well-known manufacturers. In the world market in this area, companies specializing in the manufacture of high-quality optics are leading. It should be noted such companies as Canon, Olympus, Pentax, Minolta, Nikon.
Pros of different manufacturers
Typically, every binocular maker does best with a touch of their own. If you are looking for mid-priced binoculars, Canon is the best choice, the company's strong point is its ability to create balanced and functional binoculars at a low cost. Small devices made in a sealed case are best managed by Pentax, although this manufacturer is considered elite, so the buyer will have to pay a fairly large amount. Nikon is considered the leader among binoculars with sharp optics.
Performance characteristics
In most cases, binoculars are not used at home, but in the field, that is, they are constantly exposed to the external environment. Indicators such as moisture resistance, as well as shock resistance are very important, because you don't want to get an item that breaks after 1 hit for a large amount. Elite models of binoculars have a body filled with nitrogen, which prevents the glasses from fogging up in conditions of large fluctuations in temperature or humidity.
Quality checking
Binoculars are a complex optical device, and you must make sure that there are no defects before final purchase. The housing must not be scratched or deformed, and the lenses must not be damaged. If you look through binoculars at a light background, you will notice the presence of dust inside, which indicates a poor tightness of the case. Ghosting and blurring of the contours of objects are unacceptable.
It is highly undesirable to buy binoculars that provide an image of a colored border around the subject. It is very important that the buttons on the housing are located comfortably in your hands, so that you can adjust the device by touch. There is another test for the quality of binoculars. In good light, you should try to read a book from a distance of 10 meters.
additional verification
You can check the binoculars more thoroughly. To test the optical quality, you need to slowly move the device away from the eye at a distance of up to 20 cm. In this case, the picture should be exactly the same, distortions are unacceptable. At a distance of up to 30 cm, the pupil of the device should remain perfectly round and well lit. If the binoculars do not have a separate adjustment for each eyepiece, you need to check the focusing on the sharpness of both parts of the device.
We wish you a good choice!
Specialized boutiques and online sites offer a huge range of high magnification binoculars from global manufacturers. However, choosing the best model is not easy. Despite the recommendations of the experts, you will need exactly the binoculars that will meet your individual needs, optimally match the performance and at the same time suit the price.
Extensive family
There is a wide range of binoculars available today. For whatever purpose you choose your device, binoculars with high magnification will always be preferable, as they provide more options. However, for everyone, these indicators will be different. Therefore, it is important to preliminarily answer a number of questions:
- How small (detached) items you want to view.
- Planning to use your binoculars in bright light or at dusk.
- A massive solid device or a lightweight version for long-term observations will be preferable for you.
How many options does a good optical specialty store have for you? Enough to get completely confused and go home without buying. However, an experienced salesperson will always help and offer to initially choose the scope of the device. It is clear that theatrical and military models will have different functionality. No need to explain when high magnification binoculars are used. In addition, there are marine models for astronomical observations, night vision or sports tracking. Each model differs significantly not only in characteristics, but also in price.
Military binoculars
In fact, whatever observation you want to do is not a theater or travel model. They have one advantage - they are lightweight. But a significant number of disadvantages negate this advantage. The best option is military models. If you need binoculars with high magnification, then this is the only optimal and reliable option. Military binoculars have the following advantages:
- larger field of view;
- high quality optics;
- the optimal magnification is 6-8 times;
- shockproof housing;
- availability of additional functions (long-range grid, stabilization);
- some models are also compact in size.
One of the highest quality military binoculars is still our domestic optical devices.
Dimensions (edit)
If you want to spend hours with binoculars in hand, then immediately think about the size of the optical device. On the one hand, the more compact the device, the better. However, the reduction in volume always occurs at the expense of reduced functionality. It also matters where the observations take place. It is worth buying the smallest model for the city. For hiking in nature, dimensions are not so critical - you can choose binoculars with high magnification and more. Plays a role and color of the body. For urban conditions, black is best, and for nature - a protective color.
Magnification factor
Binoculars with high magnification have different magnifications. Everything is quite simple here, the closer you want to see distant objects, the larger the numbers should be. The maximum approximation can be estimated in the store. Every person's vision is different. What will be comfortable for one person may not be suitable for another at all. In fact, it is not at all necessary to strive to buy a device with the maximum multiplicity. This is not an absolute value, and it should be considered exclusively from the point of view of the tasks being solved. For standard field hand-held observations, instruments with a magnification of 6-8 are used, and the maximum value will be 10x magnification.
Binoculars with high magnification (15-20x) are used with a tripod. To fix the device, special adapters are used. However, there are some drawbacks here, they are not suitable for long-term wear. In addition, in conditions of limited visibility (forest), where there are many natural obstacles on the ground, a large magnification is useless.
Agree, it is very convenient to make this indicator adjustable. Expensive binoculars with a large increase in Russian production are pankratic, that is, with variable magnification. Optical devices of the Baigish brand (Kazan) and TENTO (Zagorsk) are popular.
The magnification of binoculars can be changed (just like with zoom lenses). However, such a device is many times more complicated, which means that the cost will be much higher (from 4 to 20 thousand rubles).
Other parameters:
- The lens diameter is indicated in the parameters immediately after the magnification. For most observations, parameters 30, 35 and 42 will suffice. For reduced illumination, parameters 42 or 50.
- Vision angle. Binoculars with a large increase in Russian production tend to give a small coverage of the terrain. And, conversely, the less powerful the device you buy, the wider the viewing angle, and, accordingly, the easier it is to navigate on the spot.
- Aperture is the square of the exit pupil diameter.
- Focus, or adjustable value.
- Depth of field is the range of distances to the observed target without changing focus.
There are a number of other parameters that can be missed. If the smallest details are important and necessary for specialists to perform precise work, then for most ordinary people they play practically no role.
Russian binoculars BPC
These devices are distinguished by an ideal price-performance ratio. They are created by specialists from the Kazan Optical and Mechanical Plant (KOMZ). A distinctive feature is excellent quality and solid performance. These are working models that will not fail in any conditions.
Among the widest assortment you can find binoculars with high magnification (100x). When choosing these devices, you can be guided by the reviews of happy owners. They emphasize that the binoculars of this manufacturer are reliable and practical. They are ideal for hunters, fishermen and outdoor enthusiasts. Not too heavy, compact, making it possible to inspect the terrain many meters ahead, despite difficult weather conditions - this is an incomplete list of the advantages of an optical device.
The most powerful device
The BPC family brings to your attention binoculars with high magnification (20-100x), in addition to classical devices with a lower magnification. In fact, such parameters are important for those who are interested in the starry sky, who conduct astrological observations of the Moon. Such optical devices usually have a "C" prefix at the end of their name. These models are distinguished by a special rangefinder and goniometric grid, which is important primarily for hunters. What is it for? To estimate the distance to the object.
Today on sale you can find models with camouflage colors, which are created specifically for hunting. Other users will be interested in the rubberized coating on the case to prevent damage, and the ruby coating on the lenses.
Binoculars "Zenith"
This is another domestic manufacturer. Buying a device from this brand, you can be sure that you are getting really worthwhile and high quality binoculars.
How do you choose good high magnification binoculars from Zenith? It is best to contact an optical store where this technique is sold. With the initial knowledge and understanding what you want to purchase, you can choose the best model for yourself. I would like to note that they are all modern and functional. With their help, you can monitor objects in the daytime and at night. The highest quality optics allow you to see the smallest details at great distances. They are deservedly popular with travelers and climbers.
Instead of a conclusion
How to choose high magnification binoculars? First of all, you need to think carefully about where you will use it. In principle, this may be sufficient if you consult a professional consultant. If you decide to study the market on your own and find your model, we recommend that you pay attention to each of the parameters that are listed in this article.
Basic parameters of binoculars
Magnification (multiplicity) and diameter of the objective lens
Usually these parameters are indicated on the case of binoculars, for example "10x40".
- The first number (10) is the multiplicity, it tells us that with the help of these binoculars we will be able to see an image of an object 10 times larger (in angular measure) than when observing with the naked eye.
- The second number (40) shows the input aperture of the lens in millimeters or, in simple terms, the diameter of its front lens. The larger the lens, the more light it collects and produces a brighter image.
Exit pupil diameter
Accordingly, for viewing from binoculars in low light conditions, binoculars with an exit pupil diameter of at least 4 mm are required, and at night, preferably 5 - 7 mm, depending on age.
Twilight factor
This is a relative value that depends on the magnification of the binoculars and the diameter of the entrance lens of the objective. In this case, the quality of the optics is not taken into account.
The twilight factor is calculated by multiplying the magnification by the front lens diameter and taking the square root of the result.
When observing in low and twilight conditions, binoculars with a higher twilight factor are recommended.
Focus mechanism
Most prismatic binoculars have a center focus. In this case, the sharpness is first adjusted for the left eyepiece (left eye) by turning the central focusing drum (wheel): then, if necessary (if the observer has different visual acuity for the left and right eyes), the right eyepiece is adjusted. In the future, the binoculars are refocused to closer or distant objects only with the central drum. There are binoculars with individual, or separate focusing of each eyepiece, i.e. the eyepieces are not linked by a mechanical system. In this case, each refocusing of the binoculars requires adjustment of both the left and right eyepieces. According to this scheme, binoculars with a rangefinder or goniometric scale, marine binoculars with a sealed case, and specialized astronomical binoculars are made. Some binoculars do not have a focusing mechanism as such: the optical system gives a relatively clear image from a certain distance to infinity, similar to a photographic lens set to a hyperfocal distance (see depth of field); tuning to distant and near objects is possible only due to the natural ability of the eyes to accommodate. The advantages of binoculars with fixed focus include a simplified design and, consequently, a reduction in cost, increased reliability due to the absence of moving parts and improved water resistance of the case.
Focusing range
Sometimes you have to look through binoculars objects in the immediate vicinity, for example, a butterfly on a flower. Such observations require binoculars with a minimum focusing distance of no more than 0.5-1.5 meters.
Multilayer enlightenment
The technical characteristics of binoculars rarely contain data on the quality of optical elements, although the final image quality depends on this:
- opaque lens reflects 4 - 5% of the luminous flux
- single-layer coated lens - about 1%
- lens with multi-layer (SMC) coating - only 0.2% of light.
Since the construction of binoculars uses not one, but several lenses, in practice, the loss of light turns out to be even greater. For example, for binoculars consisting of 6 uncoated elements (12 surfaces), the light loss will be about 40%, while for the same design with lenses with SMC-coated lenses - only 2.4% (that is, 17 times less). Optical coating also minimizes internal reflections, improving image clarity, color reproduction and contrast.
Accordingly, according to the color of the outer lenses of the binoculars, it is already possible to draw certain conclusions - what quality of the lens and with what type of coating they are made.
Aspherical elements
Stakeout eyepiece
Many binoculars have an extended eyepiece due to the large focal length of the eyepiece. This means that while observing, you can hold the binoculars at some distance from your eyes and still see the full image. In this case, it is possible to look through binoculars with glasses without deteriorating the image.
New properties
Image stabilization is one of the new features of modern binoculars. These binoculars have two gyroscopes powered by built-in batteries. They are enough for several hours of work.
Types of binoculars
- Sports binoculars
- Free focus binoculars
- Rangefinder binoculars
- Binoculars with built-in compass and rangefinder
- Gyro-stabilized binoculars
- Binoculars for viewing platforms
Notes (edit)
see also
Links
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Synonyms:- Ushakov's Explanatory Dictionary
- (French binocle, from Latin bini pair, two and the oculus of the eyes), optical. a device for visual observation of distant objects with two eyes, as well as for measuring angles and distances. Consists of two telescopes connected so that their optic. axles ... ... Physical encyclopedia
- (Binocle, binocular) an optical instrument consisting of two connected telescopes for viewing distant objects. Samoilov K.I. Marine dictionary. M. L .: State Naval Publishing House of the NKVMF of the USSR, 1941 Binoculars ... ... Marine dictionary
Binoculars- prismatic, with a reversing prism system. BINOCLES (French binocle, from the Latin bini pair, two and the oculus of the eyes), an optical device of two parallel telescopes for observing distant objects with both eyes. Binoculars ... ... Illustrated Encyclopedic Dictionary
- (French binocle from Latin bini pair, two and the oculus of the eyes), an optical device for viewing distant objects with both eyes. Consists of 2 telescopes connected in parallel. Gives 2 22 times magnification ... Big Encyclopedic Dictionary
BINOCULARS, an optical device, into which one looks simultaneously with two eyes. Gives a magnified view of a distant object or area. Consists of a pair of identical telescopes (one for each eye); it has a lens with a lens, ... ... Scientific and technical encyclopedic dictionary
BINOCULARS, me, husband. A handheld optical device consisting of two parallel-connected telescopes for viewing distant objects. Field b. Theater b. | adj. binoculars, oh, oh. Ozhegov's Explanatory Dictionary. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 ... Ozhegov's Explanatory Dictionary
Male, lat. double telescope, two-eyed mazuriks. Dahl's Explanatory Dictionary. IN AND. Dahl. 1863 1866 ... Dahl's Explanatory Dictionary
Present, number of synonyms: 3 two-eyes (1) stereo binoculars (1) telebinoculars (1) ... Synonym dictionary
Each of us had to use binoculars, or at least see it from the side. This device consists of two telescopes connected on a rigid frame, and allows you to obtain an enlarged stereoscopic image. To an inexperienced person it may seem that choosing binoculars is easy, but in fact it is not. In addition to the degree of magnification of the image of each model, there are many more parameters to consider when buying.
Types of binoculars
All binoculars are divided into two groups - made according to Galileo's optical system and Kepler's optical system.
- Galileo system
Galileo binoculars use one or more concentrating lenses and one diffusing lens. These devices give a direct picture and there are no additional elements in their design. Galileo's optical system is used to produce theater binoculars.
- Kepler's system
Most binoculars use the Kepler optical system. It consists of several concentrating, long and short throw lenses. This system gives an upside-down image, therefore, reversible lenses are added to it, which allows you to "unfold" the image and reduce the size of the binoculars.
Wrapping lenses in Kepler binoculars are divided into two types:
Roof prism - all optical elements are located on the same axis;
Porro prism - optical axes of long-focus and short-focus lenses.
The lenses are spaced apart.
Magnification factor of binoculars
The designation of most existing binoculars consists of two numbers, the first of which is the magnification factor. For example, when binoculars are labeled 8x50, their magnification is 8. This characteristic indicates how close the image of the object you are looking at will be. So, if you point eight-fold binoculars at an object located 80 m from the observer, then it will look as if it is located 10 meters away.
Based on the magnification, all binoculars are divided into:
2-4 multiples;
4-8 multiples;
Binoculars with a magnification of 8 and higher.
When choosing the magnification of binoculars, you need to proceed from the maximum distance at which objects of interest can be located.
When buying, keep in mind that the higher the magnification of the binoculars, the harder it is to achieve a clear and stable picture. Devices with a magnification greater than 10 allow you to get a high-quality picture only when using a tripod (or by resting the binoculars on a stationary object). Binoculars with a magnification of 4-8 times are considered optimal for everyday use. They are lightweight, comfortable, allow you to quickly freeze the image and achieve high stability when viewing.
We should also mention binoculars with zoom and automatic image stabilization. These devices allow you to smoothly change the magnification ratio and compensate for hand fluctuations, providing a clear picture. These binoculars have several drawbacks. They are heavy, expensive, and more delicate than conventional models.
Outer lens diameter
The outer lens diameter is the second number in the binocular designation. For example, 8x40 binoculars will have an outer lens with a diameter of 40 mm. The larger the outer lens, the more light it will collect, and the brighter the resulting image will be. The reverse side of the coin is the weight of the binoculars, which increases with the increase in the lens diameter. In normal light, a lens with a diameter of 20-25 mm is sufficient for operation. Such binoculars will be much lighter and more compact than its "twilight" counterpart with a 35-40 mm lens.
Lens material and coating
The most common lens materials are glass and plastic. Binoculars with glass optical elements provide better image quality, while those with plastic ones are much cheaper. Lenses may have special coatings to improve their performance. There are markings for such coatings:
C - the coating is applied in one layer to individual lenses
FC - the coating is applied in one layer to all lenses
MC - coating applied to some lenses in several layers
FC - all lenses are multi-coated
Exit pupil diameter
The exit pupil diameter is the size of the light beam that hits the observer's eye. This parameter can be found by dividing the size of the outer lens by the multiplicity. For example, 8x40 binoculars have an exit pupil diameter of 5mm. The luminosity depends on this indicator. It should be 4-7 mm - this is the average size of a human pupil.
Light transmission coefficient
Light transmittance is the amount of light that passes through all the lenses of a binocular without loss. This parameter depends on the quantity and quality of refractive elements, the presence of an antireflection coating on them and the quality of the assembly. The higher the ratio, the brighter the image will be. For top models of binoculars, it can reach 97%. Values of light transmittance from 94% and above are considered acceptable.
Aperture ratio
Aperture - the value of the brightness of the picture, which is indicated by a number equal to the square of the diameter of the exit pupils. This parameter is critical for those who often use binoculars at night.
Focus mechanism
Each person has their own unique vision. To compensate, a focusing mechanism is used that allows you to adjust the sharpness to the individual characteristics of the eyes. There are two focusing systems - separate and central.
- Separate focusing system
Most often used in full-size binoculars with high demands on reliability and image quality. It consists of two separate adjustment mechanisms for each eyepiece. The advantages of a separate focusing system are the ability to fine-tune the sharpness separately for each eye, high reliability and unpretentiousness of the mechanisms. Its disadvantages include heavier binoculars and an increase in their dimensions.
- Central focusing system
The central focusing system is most often used in compact binoculars. It consists of a diopter adjustment ring located on the eyepiece and a center focusing drum. To adjust, you need to close one eye, use the diopter adjustment ring to set sharpness for one eye, and then, opening the other, achieve final sharpness using the central focusing drum.
The advantages of this focusing system are the speed and ease of setup, as well as the low price and compactness of the binoculars in which it is used. Its disadvantages include not as good a depth of field as that of a separate system. This type of focusing is not suitable for people with different eyesight.
Choosing binoculars for specific purposes
Binoculars are often purchased for specific purposes. The main areas of application of binoculars and their parameters are listed below.
Depending on the performance characteristics, there are:
Theater binoculars - These are used to observe nearby objects. These binoculars have a small magnification (X2.5-5), good viewing angles, large aperture and compact dimensions;
Compact binoculars - these devices are small in size, while at the same time they have great power of magnification. These binoculars have small lens diameters and low luminosity. They are used in good lighting conditions;
Field binoculars - devices have good aperture (front lens size 30-50 mm), and have good magnification (from X8 to X20);
Military binoculars are compact and lightweight devices with a durable, dust and water resistant housing. They have good magnification and large viewing angles;
Marine binoculars - differ from other binoculars in their waterproof coating and the use of a multi-layer lens coating, which provides high light transmission. These binoculars have a high magnification, they often have a built-in rangefinder and compass;
Night vision binoculars are compact and lightweight devices that have good viewing angles and allow you to see at night thanks to the built-in IR illuminator.
Tips for those looking to buy binoculars
Buy binoculars from renowned manufacturers. Pay attention to the products of ATN, Bushnell, Gamo, Nikon, Olympus, Tasko and others.
Choose the correct magnification of the binoculars. If a strong magnification is not needed, then it is better to buy binoculars with good viewing angles and higher aperture.
When buying, thoroughly test the binoculars - check the operation of all movable joints, try to look at objects located at different distances, inspect the case and lenses for mechanical damage, and so on. Ask waterproof binoculars to be immersed in water, and after removing and drying, check that the image quality remains the same.
Make sure that the image does not double, does not distort, and that you do not feel pain in your eyes after a few minutes of using the binoculars. Such phenomena can be caused by the most common factory defects - poor-quality lenses or axial parallelism disturbed during the assembly process.
You have decided to opt for binoculars. Where to begin? It all depends on your future plans. If you are going to take it with you on a hike, on a hunt, on an expedition - you need field binoculars
But a sporty one may also work. Sports binoculars can be a good gift for a teenager. If you love extreme sports or go to a friend's or boss's birthday and want to show that you think he is a really cool man, night vision binoculars will come in handy. A present for your beloved mother-in-law - theatrical binoculars. If you are a shipowner or a fan of astronomy, then you will probably need binoculars with powerful magnification.
Main characteristics of binoculars
What are the characteristics of these models differ?
The defining property of binoculars is increase (multiplicity)... This is the ratio of the size of an object when magnified with binoculars to its size visible with the naked eye. This characteristic in modern binoculars ranges from 3x magnification (theater binoculars) to 22x (heavy powerful binoculars are usually used with a tripod).
By magnification, binoculars can be divided into groups:
- small magnification (2-4 times)
- medium magnification (5-8 times)
- large magnification (10-22 times).
Let's add right away that chasing magnification to the detriment of other characteristics of binoculars is about the same delusion as wanting the maximum number of megapixels from a digital camera: first you need to understand what magnification is required for your specific tasks.
Most of the mid-range binoculars produced fall into the mid-range. It is quite enough for a tourist, hunter or sportsman. Inexpensive sports binoculars have 4-5x magnification. Binoculars with a magnification of 7-10 are considered good. It should be noted that 10x magnification is the maximum at which it is possible to use binoculars while holding them. At higher magnifications, image vibration increases so much that a tripod or built-in IS is required. By the way, the weight of powerful binoculars is such that probably no one wants to hold them in their hands for a long time: 1.5-2 kg, or even more. When buying a powerful binocular, you should pay attention to whether it has a threaded hole for mounting on a tripod.
Exists binoculars with adjustable magnification (with "zoom"), but they are more complicated and, as a result, more expensive. In addition, these binoculars are capricious to handle. Note that in terms of their optical characteristics, binoculars with a fixed magnification are better than analogs with a zoom, since it is not possible to provide high image quality at all magnifications.
The next important characteristic is diameter of the lens (entrance pupil) of binoculars(mm). These two parameters, as a rule, set in the most general form the characteristics of binoculars, for example: 6x35 means a magnification of 6x, a lens - 35 mm. Since the parameter is associated with the lens diameter binoculars When choosing a diameter, it is necessary to decide under what illumination you will mainly use binoculars. In low light conditions, the lens diameter should be larger. On the other hand, a lower magnification ratio allows observation in lower illumination with the same objective size: 7x50 binoculars have better illumination than 10x50 binoculars.
Universal for use in field conditions, hunting, etc. are binoculars with parameters 6x30, 7x35, 8x40. If you need to observe very distant objects in the daytime, you should give preference to binoculars with 8-10x magnification and a lens diameter of 30-40. If the observation will take place at reduced illumination, at dusk or at dawn, then you need to choose a larger diameter, and, possibly, sacrifice the magnification, stopping at the ratios 6x42, 7x42, 7x50.
Exit pupil size binoculars are defined as the ratio of their diameter to the magnification, say, for 6x30 binoculars it is 30: 6 = 5. The optimal ratio is considered to be close to the diameter of the pupil of the human eye (7 mm).
Another important physical characteristic of binoculars is field (or angle) of view... It is usually set in degrees and defines the width of coverage of a given visual device. Note that this value is related to the ratio of inverse proportion with magnification: the more powerful the binoculars, the smaller its field of view. Large field binoculars - wide-field or wide-angle.
Depth of field- the range of distances to the target in which it is not necessary to change the adjusted focus. It is not indicated in the parameters of binoculars as an indicator, but it is important to take into account that it decreases with increasing magnification of the binoculars.
Three-dimensional image (also called stereoscopicity or plasticity) ensured by the binoculars' periscope - a property in which the lenses (outlets) of the binoculars are set wider than the eyepieces (inlets). Stereoscopicity is considered a plus, for example, in the field. In the theater, on the contrary, it interferes with the perception of what is happening on stage, therefore theatrical binoculars are designed so that the distance between its lenses is equal to the distance between the eyepieces.
Wrapping system device
According to the internal structure, binoculars are divided into binoculars with a prismatic and lens reversing system, but the latter is practically not used in modern binoculars, since it requires a longer length of the telescopes. The most commonly used prism wrapping system proposed by the French optician Porro.
In addition, modern binoculars often use wrapping systems with special prisms that have a "roof", that is, two faces located at right angles to each other and similar to a gable roof.
Focusing
The central focusing method is a universal method of focusing, it allows you to quickly focus the binoculars, observing, for example, a moving object. However, split focus binoculars are more reliable. In addition, they provide better conditions for people with significantly different levels of vision in the eyes. Some of these binoculars have divisions for focusing in accordance with the level of vision: so that a person, knowing the diopter of their eyes, can immediately adjust the eyepieces. Binoculars with center focusing sometimes have a mechanism for adjusting the eyepieces to adjust for different eye diopters.
There are also focus free and autofocus binoculars, which, as a rule, provide not very high image quality, but are convenient for situations in which long adjustments are impossible, for example, for firefighters or rescuers, as well as for observing a rapidly moving object.
Removal of the exit pupil- the distance to the eyepiece, at which the binoculars can be focused. With a distance of 18-20 mm, observation can be carried out with glasses or, for example, in a gas mask. For ordinary binoculars, this distance is 10-12 mm. Binoculars with removal of the exit pupil can be used without glasses: the eyepieces are "lengthened" with soft plastic rings.
The night vision- night vision binoculars form a separate group of devices using infrared radiation. An additional important characteristic for them is the continuous operation time of the power supply. The presence of IR illumination for work in extremely dark conditions is essential, as well as a protection system in case of accidental activation in bright light.
Who needs what kind of binoculars
When choosing binoculars, it is worth considering all the characteristics described, and which one to pay special attention to depends on how the binoculars will be used. Here are some practical tips for different binoculars users.
For hunters, researchers, tourists and naturalists the resistance of the binoculars to weather surprises is important (waterproof coating, the so-called "rubberized" binoculars), as well as to unexpected shocks and falls. There are binoculars in a sealed case, filled with dry nitrogen and equipped with moisture absorption devices - this helps to fight freezing and fogging of the device.
In the mountains, it is more convenient to use binoculars with a wide field of view. In the forest, a greater depth of field is preferable.
Those who are going to look at animals and birds through binoculars should pay attention to the surface and covers of the binoculars: if they are matte and dim, this will help not to scare away the watched.
If you are an ornithologist and study bird life in nests, it is useful for you to know that some mid-range binoculars do not have a manual focus mechanism: they focus automatically, but only at distances exceeding 20 m. At a closer distance to the subject, they are difficult to use.
Binoculars for the amateur astronomer
If you want to see the details of the planets, the rings of Saturn and the relief of the lunar surface, then powerful binoculars with a magnification of 20x and higher will do. If you set your goal to examine distant planets, like Uranus and Neptune, or study lunar craters in detail, get to indistinguishable galaxies and nebulae, you will need a telescope. These two devices perfectly complement each other, because binoculars, due to their stereoscopic properties, have a number of advantages over a more powerful telescope in magnification. For general acquaintance with the sky, binoculars with 10x50 characteristics can be a good option. A large field of view allows you to navigate in the observation area, moreover, you can view the sky while holding binoculars in your hands, and not catch a trembling object in the lens, as you have to do at higher magnifications.
Some astronomers find it convenient to use binoculars with the exit pupil distance: rubber rims on the eyepieces, about 2 cm wide, help protect the eyes from side light, such as lunar light.
Shipowners and sailors Binoculars with image stabilization are generally used because deck swinging interferes not only with handheld observation, but also with tripod use.
Important notation
Finally, there are a few important conventions that can be encountered when choosing binoculars.
Binoculars of domestic manufacturers are often denoted by abbreviations such as BPShTs 8x40 or BPC 20x60, in which
- "B" stands for binoculars,
- "P" - prismatic,
- "G" - Galileo,
- "K" - compact,
- "P" - field, "T" - theatrical, "S" - sports, "V" - high aperture, "B" - high magnification, "W" - wide-angle, "C" - center focusing, "F" - internal focusing ,
- "O" is the extended exit pupil.
Foreign manufacturers have adopted, in particular, the following designations:
- l.e. - removed exit pupil,
- w.a. - wide-angle,
- Spot - large depth of field, no focusing.
- UCFmini - ultra compact;
- UCF V - compact, Porro prisms;
- DCF - compact "with a roof";
- CF - standard size, Porro prisms;
- PCF III - standard binoculars, Porro prisms;
- WP - waterproof, up to a depth of 1 m;
- PIF - expensive waterproof binoculars, 5m depth, filled with dry nitrogen, multi-layer coated, separate focusing;
- EXPS - high grade binoculars;
- HR - high quality;
- IF - with distance scale;
- BD - with laser rangefinder;
- IS - optical image stabilization;
- AF - autofocus;
- B after lens size - Glasses (from German Brille). With the removal of the exit pupil.
- N - night vision binoculars.
Here are a number of disadvantages of low-quality binoculars that can adversely affect vision with prolonged use of such a technique. First of all - a blurry or colored image, as well as its flashing with white light, especially at the edge of the field of view. If such problems arise, as well as difficulties in aiming the binoculars at sharpness or double vision of the object, it is better not to use such binoculars. The declared high magnification of binoculars at their small size and cost, the combination of "zoom" with a low price can serve as a "danger signal" for the buyer.
When choosing binoculars, it is worth checking the softness of the adjustment knobs, the convenience of the location of the buttons, in particular the stabilizer buttons, go out into daylight with the binoculars, try reading a book at a distance of ten meters.
