Bird watching has been a favorite pastime around the world for many centuries.
The ancient Romans spent time in the garden comparing the birds to one another. The children of that era would watch for hours according to some literature, sometimes comparing the wingspans of different bird species. Dating back to the beginning of time, bird watchers can be found. There are avid bird watchers even today. With the use of newer technology, you can spend hours waiting for the American eagle then snap a photograph through your binoculars.
The key piece of equipment for bird watchers is binoculars. Young or old all would agree that it is impossible to bird watch without a pair of binoculars. There are several different binoculars on the market today. All have their pros and cons. Some are better optically while others excel in cost.
A typical bird watcher will tell you that an important feature to look for in binoculars is how tough they are. To keep the binoculars in perfect viewing order they will need to work even after being dropped. A lot of binoculars are ruined when dropped accidentally. This is called some “Bash ability”. Although not a typical word it explains it well. If they fall too many times will they still work? So the “Bash ability” factor is also important to look at when purchasing binoculars.
If you are going to take up bird watching you need to keep these things in mind. When looking for a pair of binoculars to buy you may have to shop around. Binoculars are your key piece of equipment. You want to look for lightweight, buying online tough, comfortable ones with clarity. The ones in the two to four-hundred-dollar price range are generally sufficient for bird watchers.
You decided to choose binoculars. Where to begin? It all depends on your future. If you are going to take it with you on a hike, on a hunt, on an expedition – you need field binoculars
But it can also be sporty. Sports binoculars can be a good gift for a teenager. If you like extreme or go to a birthday party for a friend or boss and want to show that you consider him to be a cool guy, you’ll need a night vision binocular. If you are a shipowner or are fond of astronomy, you will probably need binoculars with a power increase.
Basic Characteristics of Binoculars
What are the characteristics of these models?
The defining property of binoculars is an increase (multiplicity). This is the ratio of the size of the object in an enlarged binocular to its size, apparently with the naked eye. This feature in modern binoculars ranges from a 3x magnification (theatrical binoculars) to 22x (heavy, powerful binoculars are usually used with a tripod).
By increasing the binoculars can be divided into groups:
- the small increase (2-4 times)
- average magnification (5-8 times)
- a large increase (10-22 times).
Let’s add at once that chasing the increase to the detriment of the other characteristics of binoculars is about the same misconception as wanting the maximum number of megapixels from a digital camera: first, you need to understand what increase is required for your specific tasks.
Most of the produced binoculars of the middle price group fall within the range of average magnification. It is quite enough for a tourist, hunter, or sportsman. Inexpensive sports binoculars have a 4-5-fold increase. Binoculars with an increase of 7-10 are considered good. It should be noted that a 10-fold increase is a maximum at which it is possible to use binoculars while holding it in the hands.
At higher magnification, the image vibration increases so much that you need a tripod or built-in image stabilizer. By the way, the weight of powerful binoculars is such that to keep them in hands for a long time, probably, nobody will want: 1,5-2 kg, or even more. When buying powerful binoculars, you should pay attention to whether it has a hole with a thread for mounting on a tripod.
There are binoculars with adjustable multiplicity (with “zoom”), but they are more complicated, and, therefore, more expensive. In addition, such binoculars are capricious in circulation. Note that in terms of optical characteristics binoculars with a fixed multiplicity are better than analogs with a zoom because it is impossible to ensure high quality of the image at all magnifications.
The next important characteristic is the diameter of the lens (entrance pupil) of the binoculars (mm). Two of these parameters, as a rule, is set in the most general form of the characteristics of binoculars, for example, 6×35 means a multiplicity of 6x, the lens is 35mm. Since the lens diameter of the binoculars is related to the diameter of the lens, choosing the diameter, it is necessary to decide the question of what kind of illumination you will mainly use binoculars. At low illumination, the diameter of the lens should be greater. On the other hand, a smaller magnification allows to observe at a lower illumination with the same lens size: for binoculars 7×50 the illumination is better than for 10×50.
Universal for use in hiking conditions, hunting, etc. binoculars with the parameters 6×30, 7×35, 8×40. If you want to observe very distant objects during the day, preference should be given to binoculars with a magnification of 8-10 and a lens diameter of 30-40. If however, the observation occurs with reduced illumination, at dusk or at dawn, then you need to choose a larger diameter, and perhaps give up an increase, stopping at the ratio of 6×42, 7×42, 7×50.
The size of the exit pupil of the binocular is defined as the ratio of its diameter to the multiplicity, say, for the binoculars 6×30 it is 30: 6 = 5. The optimal ratio is close to the diameter of the pupil of the human eye (7 mm).
Another important physical characteristic of a binocular is the field (or angle) of vision. It is usually set in degrees and determines the width of the coverage of this visual device. Note that this value is related to the ratio of the inverse proportion to the increase: the more powerful the binoculars, the smaller its field of view. Binoculars with a large field – wide-angle or wide-angle. Forgoing outdoor in summer should consider choosing hiking sandals.
The depth of field – the range of distances to the target, in which you do not need to change the adjusted focus. It is not indicated in the parameters of binoculars as an indicator, but it is important to consider that it decreases with increasing binocular magnification.
The volume of the image (it is also called stereoscopic or plasticity) is provided by the periscopic of the binoculars-a property in which the lenses (exit holes) of the binoculars are diluted wider than the eyepieces (the entrance apertures). Stereoscopy 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 the stage, so the theater binoculars are designed so that the distance between its lenses is equal to the distance between the eyepieces.
Turning system device
On the internal device, binoculars are divided into binoculars with a prism and lens wrapping system, but the latter is not used in modern binoculars since it requires a longer length of telescopes. Most often used prismatic 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 that are at right angles to one another and resemble a gable roof.
Who needs what kind of binoculars?
When choosing binoculars, it is necessary to consider all described characteristics, and which one to pay special attention to depends on how the binoculars will be used. Here are some practical tips for different users of binoculars.
For hunters, explorers, tourists, and naturalists, the stability of binoculars for weather surprises (moisture-proof coating, so-called “rubberized” binoculars) is important, as well as, to unexpected shocks and falls. There are binoculars in a sealed enclosure filled with dry nitrogen and equipped with moisture absorption devices – this helps to fight the frost 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.
For those who are going to look through the binoculars of animals and birds, it is worth paying attention to the surface and covers of binoculars: if they are dull and soft, this will help not frighten off the observed.
If you are an ornithologist and study the life of birds in the nests, it is useful for you to know that some middle-price binoculars do not have a manual focus mechanism: they focus automatically, but only over distances exceeding 20 m. If you are closer to the object, it is difficult to use them.