How to choose a power zoom lens?

In general, the power zoom lens zoom ratio is relatively large, commonly used 6 times, 7 times, 10 times the lens, the focus is mostly below 100mm, there are 15 times, 16 times, 20 times, 22 times, etc. Most of the focal lengths are between 100mm-300mm, and there are still 30 times, 33 times, 50 times, and 100 times. The general focal length is more than 300mm, and some can even reach or exceed 1000mm, especially suitable for ultra-long distances. monitor. Different from a manual zoom lens, the focal length of the power zoom lens can be artificially changed by the rear end, and the key part of the scene can be zoomed in and observed. The monitoring effect is very good. At present, as is the case with manual zoom lenses, high-end technologies and products are in the hands of most Japanese manufacturers. As we all know, in the past half century, Japan’s optical industry has developed quite rapidly. Currently, the global high-end CCTV lens market is almost Monopolized by Japanese brands, especially the zoom lens. The development of the electric zoom lens requires a very deep optical technology and a large amount of research and development funds. The manufacturers of the electric zoom lens product line are very few globally, and the price of the electric zoom lens is generally more expensive. In China, there are also individual manufacturers that produce electric zoom lenses. Basically, they were transferred from former military companies or optical institutes. Because of the production of electric zoom lenses, they are influenced by many aspects such as design, raw materials, and key technologies. Although the company has a very good design, due to the constraints of other conditions, it can be produced and sold. In fact, it is very rare, and the effect is not good. Of course, there are only those fake products that mimic the Japanese brand. Even more flattered.

Manual zoom lens and power zoom lens

First of all, everyone must understand that the development principle of the power zoom lens is not the same as the manual zoom lens. The power zoom lens is a perfect combination of light, machine, and electricity. The development of electric zoom lens requires a very deep optical technology as the basis, and at the same time need to invest a lot of research and development funds, which is currently on the market can have a wealth of electric zoom lens product line manufacturers are very few, and the price of power zoom lens The main reason is very expensive. In fact, the large power zoom lens needs to solve many optical problems in the process of development, such as longitudinal chromatic aberration and unfocused problems. It is not a manufacturer that can do manual zoom lens can do electric zoom lens, for example, at present in China. Manual zoom lens sales of several better brands, and some almost no power zoom lens, and some have several such as 10-200mm, 10-300mm, but the effect is very bad, focusing is not true, low resolution. In fact, this is in itself a manifestation of the strength of the company. It is not that these companies do not want to do it, but it cannot be done due to various reasons such as technology. So I hope everyone will first distinguish the manual zoom lens manufacturer from the motorized zoom lens manufacturer. Only a handful of manufacturers, such as Toshiba and Fujinon, which have invested in R&D for the power zoom lens for many years, can produce satisfactory products. At the same time, if Japan’s Toray is rich in power zoom lenses, it is also rich. The manufacturers of manual zoom lenses are even rarer.

First-tier vendors and second-tier vendors

Manual zoom lens CBC, Tamron, Tuli Precision, Fujinon,

The power zoom lens is Toray, Fujinon, Pentax CBC, KOWA, the above are foreign manufacturers, domestic manufacturers have electric zoom lens POMEAS, they have been providing OEM services for the above foreign manufacturers, so the quality is not better than foreign brands The difference, relatively speaking, the price is also much more affordable than foreign.

Electric zoom lens and one machine

With the rise of the all-in-one, many engineers believe that the era of electric zoom lenses has passed. Because it is easy to install and debug, the all-in-one machine is very popular because it is cheap. In fact, the rise of all-in-one machines does have a certain impact on the sales of electric zooms. In particular, the current sales volume of small-size electric zoom lenses with 10 times or less does have a tendency to decrease, but for medium and long focal lengths, electric zoom lenses One machine is still unattainable. The all-in-one uses a 1/4"-inch CCD as an imaging element. The small-size CCD is destined to have a wide-angle lens rather than a telephoto lens. The 22-inch all-in-one is currently used in the market as an example. The customer has a feeling that this 22x lens is very powerful, but the telephoto is not that far. In addition, the general electric zoom lens is fitted with a 1/3” or 1/2” inch gun CCD camera. Compared with the small size CCD of one machine, it is not the opponent of the former in many aspects such as dynamic range, illuminance, sharpness, stability, etc. Many engineers have such a feeling, one machine is convenient, but the imaging quality and stability Sex can't be compared to a gun camera.

In addition, the core of the all-in-one is automatic focusing. (The simple all-in-one without automatic focusing function is superfluous in the author's opinion), but the focusing system works after the zoom system, and the effects and speeds are different. Some common ones The machine often found that after zooming, it takes 1-2 seconds to focus, and the focus is not true. If the monitor requires frequent use of the zoom function, it is easy to happen that the entire screen is always in the focus process, and the scene cannot be watched in time. It will be inconvenient in actual use. In addition, autofocus technology has always been the forefront of technology, many camera manufacturers have been studying to improve its speed and accuracy, the current application of autofocus in our security industry are the product of several generations ago, the effect is large Discounted, so we must have this experience, the effect can be seen on the monitor screen, but once the playback through the DVR will have a big discount effect, this is because the DVR playback, the original human eyes in the viewing dynamics The delay effect on the screen makes the fact that the focus is not realistic. At this point, the power zoom lens can adjust the depth of field to open the aperture to the maximum at the telephoto end. After the focus is accurate, the telephoto end can remain clear from the telephoto end to the wide-angle end and be played back in the DVR. The frame can also be clear frame frames.

In conclusion, in the monitoring of medium and long focal lengths, the power zoom lens cannot be replaced by an all-in-one camera. This point is also in line with the actual market conditions. In remote control scenarios such as roads and forest fire prevention, and where there is a high demand for image quality, everyone must also use a power zoom lens.