"Selection" from the literal meaning can be understood as the choice, purchase, in fact, through the comparison of the goods, from the choice of the goods they need to buy. If you choose goods without a clue, first look at anti-counterfeit signs, brand, product quality, and is the price, if the price is different, then the only goods are three.
Buying clothes is actually very simple. It looks good and looks comfortable, but if it's a technology product, there are many things to pay attention to. For example, you have to look at the parameters of the product, or the hardware facility of the product, and this will require the purchaser to have a certain understanding of the product, the value of the product, and the differences between the different parameters and the hardware facilities, and take the night vision examples for example, such as the 20mm caliber lens and the 40mm caliber. What is the difference between the lens, the difference between the double barrel and the single barrel, the 2 times the rate and the 5 times the ratio, and so on, in fact, it is certain that the price of the night vision instrument of big lens and magnification must be a little more expensive. Second, look at additional conditions, such as brand, product characteristics, price, etc.
A good brand naturally does not need to worry about the quality of the product. Even if it is concerned, it can be verified according to the testing method provided by the brand.
1. How to choose the night vision instrument
The night vision instrument, in addition to the observation and use in the night, is also different in style and type, which can be divided into head wearing night vision instrument, handheld night vision instrument and night sight sight. The subdivision includes monocular single cylinder, binocular binocular, binocular single tube night vision instrument and so on. Head wearing night vision instrument is usually a combination of helmet, spinning frame and night vision instrument. It is small and portable. It can be worn on the head and adjust the direction of the lens. It saves the support of the hands. It is very suitable for a person who is not convenient to take the machine; the handheld night vision instrument is very widely used and some models are used. It can also be used as a head wear type. If the handheld is simple, you can choose a slightly larger size and multiplying model. The night sight sight is also small and portable. It can be installed on the shooting equipment according to personal needs, and the night sight sight is very demanding for the definition of the product.
Night vision equipment is chaotic in China's market, counterfeit goods and imitation goods are rampant. Although the appearance of imitation products is the same as that of big brands, the image intensifier is completely different. Do not think of the same thing, the effect is the same, buy the imitation of the market, many machines even the most decent packaging is not, it is difficult to guarantee the quality. So in the purchase of night vision instrument, we must choose a reliable big brand, one in quality can be assured, two in the later maintenance and maintenance have certain guarantee. For example, the quality of products produced by American doctors like this big brand is excellent.
3. Lens caliber
The function of a product is very important to the product itself. The more functions a product contains, the more it can reflect the value of a product. In the same way, the hardware facilities of the product can also affect the function of the product, such as the size of the lens, the lens caliber of the general night vision instrument is divided into 21mm, 24mm, 25mm, 28mm, 44mm, 50mm, 60mm, 80mm. The same image intensifier tube, the larger the aperture, the wider the scope of observation will be. But the size of the caliber will also affect the style of the night vision instrument, such as the headwear night vision instrument is not suitable for the selection of too large caliber, because the larger the diameter, the heavier the weight, wearing the head on the contrary will affect the use effect, like a handheld night vision instrument can choose a large number of caliber, watching the effect will be great.