When you are in an unfamiliar area, especially if the map is not sufficiently detailed with conditional referencing of coordinates or with no one at all, there is a need to focus on the eye, determining the distance to the target in various ways. Experienced travelers and hunters determine the distances not only with the help of many years of practice and skills, but also with a special tool – a range finder. Using this equipment, the hunter can accurately determine the distance to the animal in order to kill him with one shot. The distance is measured by a laser beam, the device is powered by rechargeable batteries. Using this device in hunting or in other circumstances, the ability to determine the distance to the eye is gradually being developed, since when using it, the real value and the indication of the laser rangefinder are always compared. Next will be described methods for determining distances without the use of special equipment.
The method of determining the distance on the ground with the help of a thumb helps to calculate the finding of both a moving and a stationary object. To calculate you need to stretch your hand forward, lift your thumb up. It is necessary to close one eye, while if the target moves from left to right, the left eye closes and vice versa. At the moment when the target is closed with a finger, you need to close the other eye, opening the one that was closed. In this case, the object will be pushed back. Now it is necessary to make a count of time (or steps, if the observation goes to a person), until the moment when the object is closed by a finger again. The distance to the target is calculated simply: the amount of time (or pedestrian steps) until the finger closes a second time, multiplied by 10. The resulting value is converted to meters.
Determining the distance to the eye
The method of recognizing the distance to the eye is the easiest, but it requires practice. This is the most common way, because it does not require the use of any devices. There are several ways to determine the distance to the target: by segments of the terrain, degree of visibility of the object, as well as its approximate value, which appears to the eye. To train the eye, you need to practice comparing the apparent distance to the target with a double-check on the map or steps (you can use a pedometer). With this method, it is important to fix in memory some standards of distance measures (50,100,200,300 meters), which are then mentally set aside on the ground, and estimate the approximate distance, comparing the real value and the reference one. The fixation of specific lengths in the memory also requires practice: to do this, you need to remember the usual distance from one object to another. It should be borne in mind that the value of the segment is reduced with increasing distance to it.
The degree of visibility and visibility of objects affects the installation of the distance to them with the naked eye. There is a table of limiting distances, focusing on which, you can provide an approximate distance to an object that can be seen by a person with normal visual acuity. This method is designed for approximate, individual finding of ranges of objects. So, if, in accordance with the table, a person’s facial features become distinguishable from one hundred meters, this means that in reality the distance to him is not exactly 100 meters, and no more. For a person with low visual acuity, it is necessary to make individual corrections regarding the reference table.
When establishing the distance to the object using the eye gauge, the following features should be considered:
- Brightly lit objects, as well as objects marked with bright color, appear closer to the true distance. This should be taken into account if you notice a fire, fire or distress signal. The same applies to large objects. The smaller ones seem smaller.
- At twilight, on the contrary, all objects appear farther. A similar situation occurs during fog.
- After rain without dust, the target always seems closer than it actually is.
- If the sun is located in front of the observer, the desired target will seem closer than it actually is. If it is located at the back, the distance to the desired target is greater.
- A target located on a level bank will always appear closer than on a hilly one. This is explained by the fact that the irregularities of the relief hide the distance.
- When viewed from a high point downward, objects will appear closer than when viewed from the bottom up.
- Objects located on a dark background always appear farther than on a light background.
- The distance to the object seems to be less if there are very few observable targets in the field of view.
It should be remembered that the greater the distance to the target to be determined, the more likely an error in the calculations. In addition, the more trained the eye, the higher the accuracy of the calculations can be achieved.
Orientation by sound
In cases where the determination of the distance to the target by the eye is impossible, for example, in conditions of poor visibility, severe terrain or at night, you can navigate by the sounds. This ability must also be trained. The identification of the target distance by sounds is due to different weather conditions:
- The clear sound of human speech can be heard from afar in a quiet summer night, if the space is open. Audibility can reach 500m.
- Speech, steps, various sounds are clearly audible in the frosty winter or autumn night, as well as foggy weather. In the latter case, it is difficult to determine the direction of the object, since the sound is distinct, but diffused.
- In a windless forest and over calm water, sounds are heard very quickly, and the rain strongly muffles them.
- Dry earth conveys sounds better than air, especially at night.
To determine the location of the target, there is a table of correspondence of the range of hearing to the characters of the sound. If you use it, you can focus on the most common objects in each locality (shouts, steps, sounds of vehicles, shots, conversations, etc.).