Most optical telescopic sight adopt Kepler telephoto system, which consists of one convex lens lens, two positive lens as the center lens, reticle wire and two eyepieces. The image it makes is inverted after the positive lens. Then it is converted into a positive image in the human eye through eyepiece transformation. Kepler telephoto system can see the details of objects more clearly and plus-sized the ability of long-distance human eyes to observe long-distance targets. And this telephoto system is easier to set up reticle!

  There is an optical hole in the optical telescopic sight system. Only when the naked eye enters the optical hole can the image be seen, and only when the optical hole enters a certain distance can the most clear full-screen imaging be seen. This distance is the exit pupil distance. Any optical observation equipment has an exit pupil distance. The difference is that the telescope of the galeriana telescope has an exit pupil distance. Generally, the naked eye can attach an eyepiece, the optical telescopic sight of Kepler telephoto system is used to prevent the rear sitting telescopic sight of the weapon from hitting the user's naked eyes, so the exit pupil distance is a certain distance from the eyepiece. A small number of military guns are aimed at with an eye mask. This eye mask prevents external light from distracting users' attention, and at the same time, it also plays a role of fixing the exit pupil distance (that is, the distance between the eyes and the eyepiece is the designed exit pupil distance)

  the larger the magnification, the smaller the field of view of telescopic sight, which is not suitable for fast target capture. If you use high magnification at close range, it is difficult to find the target at once. Generally speaking, if you use a gun aiming at a distance within 100 meters, 4 times is a common magnification. If you use it, the range can be 3-6 times. However, if the medium and long distance distance is used, a multiple of a large magnification can be used, which can be even 24 times as the case may be. In theory, the higher the magnification, the stronger the accuracy. However, the higher the magnification, the gun aiming needs to meet the requirements of accuracy. The cost is also significantly improved!

There is no special rule to say how much distance * times must apply. Completely look at environmental factors (because the larger the magnification, the less the light intensity of the gun aiming, and the smaller the field of view, if the ambient light is not strong, although the distance is far away, it is still very difficult to observe with a particularly high multiple shot!) And personal habits determine!