That means binoculars 30x60? How to determine the magnification of the binoculars
In our time in wanting to purchase a quality modern binoculars plenty of opportunities. Range of diverse equipment from world manufacturers is extremely high, including in online stores. But it is best to choose one that will suit you on the technical parameters and at the same time satisfied with the price.
This device is quite complicated in technical terms, and the ordinary consumer is sometimes difficult to understand its characteristics. For example, which means "binoculars 30x60"? Let's try to find out.
What are binoculars
Getting to the selection, decide what approach you enough for observation, will you use the device not only in bright light, but in dusk, do you need a lightweight version, with which it is possible for a long period of observation? For the same binoculars 30x60 reviews can be very different depending on the needs of the owner.
Therefore, it is important to decide what it is you are buying this device and under what conditions going to use it.
Binoculars can be theatrical and military, naval, or night vision, and a small compact for those present at the stadium during the competition. Or, on the contrary, large designed for observational astronomers. Each of the varieties has their own characteristics. Sometimes they differ quite substantially. To make a good choice, get acquainted with the basic of them.
What is the multiplicity?
This is one of the most important characteristics of such a device, like binoculars. The multiplicity tells us about the ability to increase the environment. If, for example, the figure — 8, the maximum approximation of the observed object you will be seen at a distance, 8 times smaller than he actually is.
Seek to buy the device with the maximum possible multiplicity is unwise. This figure should correlate with the circumstances and place of use of the binoculars. For observations in the field made use of the technique with digits of multiples of 6 to 8. The magnification of the binoculars in the 8-10 time — limit in which you can monitor with it. If it is higher — to prevent jitter, increased to the same optics.
Binoculars with a significant increase (15-20 fold) used in kit with tripod, which is attached through a special adapter or the adapter. Weight and dimensions do not have to long wearing and in most cases not necessary, especially when the view is obstructed by many obstacles.
Models are available with variable magnification (zoom). The magnification changing manually, like camera lenses. But due to the increased complexity of the device they are more expensive.
Which means "binoculars 30x60", or Talk about the diameter of the lens
Marking of any of the binoculars contains the size of the diameter of the front lens it is the lens that is directly after the index of multiplicity. For example, which means "binoculars 30x60"? These figures are deciphered thus: 30x – indicator ratio, 60 – the size of the diameter of the lens in mm.
The diameter of the lens affects the resulting image quality. In addition, they determined the amount of light collected by the lens of the binoculars — it is the wider, the larger the diameter. Universal for marching conditions are the binoculars marked 6х30, 7×35 or 8×42. If you plan in the daytime to observe in nature, and considered to be quite distant objects, take the device with magnification of 8 or 10x and lens diameter of 30 to 50 mm. But in twilight they are not too effective because of less light falling in the lens.
Best binoculars for spectators at sporting events — a small (pocket version) with the settings about 8х24, they are a good fit for the overall plan.
If the light is not enough
In poor light conditions (dusk or dawn) you must either prefer a device with a large diameter lens, or to sacrifice multiplicity. Optimum can serve as the ratio of 7×50 or 7х42.
A separate group, the so — called night binoculars – active and passive night vision devices. A passive lens provided with a multilayer coating that eliminates glare. They are used with minimal lighting (e.g., moonlight). Active devices work in complete darkness because they use infrared radiation. Their disadvantage is the dependence from the power source.
Fans to study space objects (for example, to consider the topography of the lunar surface) need a fairly powerful binoculars with a magnification of at least 20x. For more detailed acquaintance with the night sky, the astronomer-fan is best to take the telescope, which in this case will not replace even the best binoculars.
What is the angle?
The viewing angle (or field) is another important characteristic. This value in degrees is the width of coverage. Setting this back dependent increase in powerful binoculars have a small "angle of view".
Having wide angle binoculars is called a wide angle (or wide-field). It is convenient to take to the mountains, to better navigate in space.
Often this indicator is not calibrated angle and the width of a segment or space, which can be viewed at the standard distance of 1000 m.
Other characteristics of binoculars
The diameter of the exit pupil is called the quotient of the diameter of the entrance pupil on the value of the multiplicity. That is, the marked binoculars 6×30 this figure — 5. The optimum number in this case about 7 mm (the size of a human pupil).
Which means "binoculars 30x60" in this case? The fact that the size of the exit pupil with this labeling is 2. This binoculars are suitable for not too long observation in good light, then the eyes are threatened by fatigue and stress. If the lighting is poor, or a long observation, this figure should be at least 5, better 7 and more.
The other parameter aperture "manages" the brightness of the image. She is in direct proportion to the diameter of the exit pupil. Abstract number, which characterizes it, is equal to the square of its diameter. Under reduced lighting, it is desirable to have this rate at least 25.
The next concept is the focus. Being Central, it is a universal tool for rapid guidance of field. Regulator it is located near the hinge connecting pipe. Wearing glasses is desirable to have binoculars with diopter adjustment.
What else is important
Other, not so global features of binoculars, however, play a significant role in his choice. Depth of field refers to the size of the segment to the observation object, which is not required to adjust the preset focus. It is the lower, the greater the magnification of the instrument.
Binoculars inherent characteristic of the human eye the property of stereoscopic (binocular), which gives the opportunity to observe the objects in the background. This is the advantage of him in front of a monocular or telescope. But it is a quality useful in the field, stopping in other cases. So, for example, in the theater binoculars it is minimized.
Systems optics binoculars are lens (theatre, Galileo) and prismatic (or field). The first is a good aperture ratio, the image, the low magnification and narrow field of view. Second, apply prism that turns the inverted image produced with the lens in the usual. This helps reduce the length of the binoculars and increases the angle of observation.
Opacity is the ability of the device to pass the light rays reflected fraction. For example, the loss of 40% of light this ratio is equal to 0.6. Its maximum value is one.
What is the body of the binoculars
Its main advantage — durability. Shockproof quality provided optinonally of the body, it also ensures reliable hold hands and moisture resistance in wet weather.
Modern waterproof binoculars are sealed so that you can some time to be under water on depth to 5 metres without damage to itself. Lens protects from fogging, filling the space between them with nitrogen. Data quality is important for tourists, hunters, naturalists. Binoculars with rangefinder will be useful to the researcher, the instrument with a soft matte finish Amateur to watch the animals.
Certain non-standard functions to specific devices, like image stabilizer, laser range finder or a built-in compass significantly increase the cost of the binoculars and welcomed only as needed. Decide for yourself if you need, for example, binoculars with rangefinder if you are ready to pay more for this option.