Surveillance lens product summary
The surveillance camera lens was the lens of a surveillance camera. As a video capture device, its resolution and resolution were higher than that of a computer video head, but lower than that of a professional digital camera or DV. Read more exciting novels for free
Surveillance camera with a lens
The surveillance camera was just a single video capture device. The resolution and resolution of the lens were higher than that of the computer's video head, but it could not catch up with professional digital cameras or DVs. In reality, cameras and lenses were mostly purchased separately. The user can calculate the focal length of the lens according to the size of the target object and the distance between the camera and the object to determine the required lens. The lens required by each user depends on the actual situation. It cannot be assumed that the camera (head) already has a lens and does not need to be equipped with another lens. The focal length of the lens determined the field of view of the camera. For example, a wide-angle lens was suitable for shooting in a large space and could capture more content. A telephoto lens was suitable for long-distance shooting and could see details in the distance. Indoors, they usually chose short focal lenses, such as 2.8mm or 3.6mm lenses, while outdoors, they chose lenses based on distance. Moreover, different focal length lenses had different imaging effects. Long focal length lenses could see more details of distant objects, but the field of view became smaller and the viewing range became narrower. Wide-angle lenses had a wide viewing range, but it might be difficult to distinguish some details. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Surveillance camera lens type
Based on context alone There were many types of surveillance camera lenses, and the following were the common ones: ** I. By focal length ** 1. ** Fixed focus lens ** - [Special characteristic: Fixed focal length.] For example, 3.6mm and 6mm fixed-focus lenses. The 3.6mm fixed-focus lens had a wide field of view and was suitable for monitoring close-up and large-scale scenes, such as the internal monitoring of small shops. The field of view of a 6mm fixed-focus lens was relatively narrow, but it could see further. It was suitable for monitoring long and narrow spaces such as corridors or specific long-distance scenes such as the entrance of a community. 2. ** Zooming lens ** - [Special characteristic: The focal length can be changed within a certain range.] The electric zoom lens could adjust the focal length remotely through the control device, making it convenient to adjust the monitoring range according to the actual monitoring needs. For example, a 2.8 - 12mm zoom lens could be adjusted from a wider field of view to a narrower field of view to focus on distant targets. ** 2. By field of view ** 1. ** Wide-angle lens ** - [Special characteristic: Large field of view, generally greater than 60 degrees.] It could cover a large monitoring range, but the monitoring distance was relatively short, and there might be some distortion at the edge of the screen. It was often used to monitor open indoor spaces or large areas around buildings. 2. ** Telephoto lens ** - [Special characteristic: Small field of view, usually less than 30 degrees.] It could monitor targets far away, but the coverage was narrow. For example, in a large warehouse, it was used to monitor the goods on the distant shelves. ** 3. By function and special lens ** 1. ** Fisheye lens ** - [Description: Field of view is close to or equal to 180 degrees or even larger. It can provide a very wide field of view and can achieve a hemisphere or even global surveillance image.] However, the image was severely distorted and required special image processing technology to restore the normal image. It was often used in places that required comprehensive surveillance, such as the central courtyard of some large shopping malls and other public places. 2. ** Pinhole lens ** - [Special traits: Small and concealed lens, small aperture.] It is suitable for covert surveillance, such as special places that require secret surveillance to ensure safety, but it must be used in accordance with laws, regulations, and ethics. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The lens structure, the surveillance camera
In terms of the structure of the surveillance camera lens, it could be divided into a large lens and a small lens. The lens had two important parameters, namely the focal length and aperture. The focal length was usually 4mm, 6mm, 8mm, 12mm, etc. The larger the millimeter, the smaller the range, but the further the distance. For example, the warehouse usually used a 4mm lens, the residential building unit door usually used a 6mm lens, and the small road usually used a 12mm lens. The aperture was the F value that appeared on the lens, generally F1.0, F1.2, F1.4, F1.6, etc. The smaller the F value, the greater the amount of light, and the more expensive the lens. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Shooting lens, product photography
Here are some shots suitable for product photography: - ** Canon EF50mm f/1.8STAR **: launched in 2015. It is Canon's third generation ultra-cheap autofocus 50mm f/1.8 lens. It is more convenient to use on crop sensors and full-frame cameras. It had a circular aperture with seven blades and a maximum aperture of f/1.8 for clearer images. It also had the fast autofocus function brought by Canon's Stepper Drive (Stellar Electromotion) technology. - ** Canon EF50mm f/1.4USM **: The price is higher than Canon EF50mm f/1.8STAR, but the small increase in the maximum aperture can significantly improve the clarity and bokeh quality. It is compact, light, and easy to store. It is a Canon lens suitable for product photography. - ** Canon EF85mm f/1.8USM **: Short focal length fixed-focus lens, slightly compressed angle of view can achieve pleasant results, bright f/1.8 maximum aperture can isolate the subject and use shallow depth of field technology, which is conducive to working in low light conditions. Each component is coated with a super spectral coating to achieve high color accuracy and contrast, which can minimize reflections, lens glare, and ghosting. The ring-shaped USM provides fast and quiet autofocus performance and full-time manual focus control. - ** Canon RF100mm f/2.8L macro IS USM**: designed for full-frame cameras of the Eos R series. Combining medium telephoto field of view, fashionable design, and close-range focusing performance, it is the ideal choice for portraits, products, and macro subjects. It has a fixed focal length of 100mm, a bright f/2.8 maximum aperture, fast high-precision autofocus, and spherical aberration control ring. The near-focus design can handle subjects up to 10.2 inches, and the super spectral coating can minimize ghosting and glare under strong light conditions. - ** Tenglong SP 90mm F/2.8 Di Macro 1:1 VP USD F017 macro lens **: The focal length is practical. Compared to the 60 macro lens, the background will not be too much trouble in the picture. Basically, you can shoot around the product. When the background was messy, it could also make the background less conspicuous and highlight the product. It could also compress the space to place more things in the same field of view, allowing the product to be taken without distortion. - ** Sima Art 50mm F1.4 DG HSM lens **: The current price is 4399 yuan, and the second-hand price is more than 2000 yuan. It's cost-effective. It was compatible with the Nikon's FTZ ring, and it worked well. The focus was accurate and the noise was low, but the weight and size were more prominent. Shooting products can get a good texture and highlight the main body, basically without distortion, and can also reduce the image interference factors when the scene is not ideal. - ** Seagull 90mm f4.5 magnifying lens (produced by Shanghai No. 2 Eyewear Factory)**: A domestic lens from more than 40 years ago. At that time, the price was 25 yuan. Now, the imaging effect of a digital camera is quite good. Aperture adjustment range of 4.5 - 16, 62 aperture blades, silver appearance small, long distance between the two sides can be transferred to a variety of digital cameras, can cover the medium frame, through the focusing tube expansion and contraction focus, four pieces of mangostana plug structure sharpness is better. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Is there a difference in the size of the surveillance camera lens
There was a difference in the size of the surveillance cameras. Different sized lenses had different viewing angles and distances. Generally speaking, the smaller the millimeter of the lens, the larger the angle of the surveillance picture, but the clearer the distance. On the contrary, the larger the millimeter of the lens, the smaller the angle of the surveillance picture, and the clearer the distance. For example, the 2.8mm focal length lens has a large viewing angle, suitable for monitoring small spaces such as storage rooms within 3 meters; 4mm can be used for indoor environments such as living rooms and small shops; 6mm is suitable for small shops or doorways of 5 - 10m; 8mm is best for outdoor roads and alleys of 10 - 20m; 12mm is mainly used for specific locations such as entrances and exits of about 20 - 30m. In addition, from the relationship between angle and distance, the larger the angle, the closer the distance. For example, the 3.6mm lens was 67.4 degrees, and the distance was 15 meters; the 6mm lens was 42.3 degrees, and the distance was 20 meters; the 8mm lens was 32.6 degrees, and the distance was 25 meters; the 12mm lens was 22.1 degrees, and the distance was 40 meters; and the 16mm lens was 17.1 degrees, and the distance was 60 meters. The common surveillance camera lenses on the market were arranged according to the size of the frame: 2.8mm, 3.6mm, 4mm, 6mm, 8mm, 12mm, 16mm, 24mm, etc. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Household Xiaomi surveillance camera lens
There were many models of Xiaomi home surveillance cameras, and the functions of different models were different. Some of Xiaomi's home surveillance cameras had higher resolution lenses. For example, the Xiaomi smart camera C500 dual camera version had four million resolution, and the angle of view was large and could be seen clearly when zoomed in. The Xiaomi smart camera C700 had eight million resolution and 4K image quality. The lens could be rotated 360 degrees horizontally and 110 degrees vertically, which could accurately identify the movement of people and prevent visual blind spots from appearing. There were also some models with multiple functions, such as infrared night vision, intelligent tracking, support for two-way voice intercom, etc., and played an important role in ensuring family safety, such as monitoring the situation at home through AI humanoid detection, AI Face Recognition, and other functions. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to choose the size of the surveillance camera lens
Choosing the lens size of a surveillance camera required a combination of many factors. First of all, the size of the monitoring scene should be considered. If it was a narrow environment such as elevators and stairs, 2.8mm focal length was more suitable; for slightly larger scenes such as conference rooms and shops, 4mm lenses were suitable; parking lots, factory workshops, courtyards and other open places, 6mm lenses could be used. From a distance perspective, different focal lengths corresponded to different effective monitoring distances. For example, a 3.6mm lens was 15 meters away, a 6mm lens was 20 meters away, an 8mm lens was 25 meters away, a 12mm lens was 40 meters away, and a 16mm lens was 60 meters away. Generally, 3.6 - 6mm cameras are within 40 meters, mostly for indoor machines or wide-angle lenses dedicated to the door; 6mm and above are narrow-angle lenses with an effective distance of about 100 meters, and 25mm lenses have an effective distance of about 150 meters. The lens equipped with the high-speed laser cloud platform machine can reach an infrared distance of 300 meters. In addition, it also needed to be considered according to the image effect of the monitoring target on the monitor and the specifications of the CCD. If you need to monitor a relatively close object and have high definition requirements, the effect of a fixed-focus lens may be better than a zoom lens. At the same time, if it is an environment with constant lighting conditions, such as a laboratory, a fixed aperture lens can be used; if the illumination changes are not obvious, a manual aperture lens can be used and a fixed value can be adjusted; if the illumination changes greatly and requires 24-hour outdoor monitoring, an automatic aperture lens should be used. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Video intercom system, dual-lens surveillance
The dual-lens surveillance in the video intercom system was used in some devices. For example, the 360 video doorbell 5 Max dual-camera version was equipped with dual lenses. The dual lens could provide monitoring from different angles or different fields of view, adding more functions and advantages to the visual intercom system. Its dual lenses could cover more areas. For example, one lens could focus on the main area in front of the doorbell, and the other lens could cover a wider range, thereby reducing the number of blind spots. This would help to have a more comprehensive view of the situation outside the door in the video intercom scene. Whether it was the location of the visitor, the appearance, or the surrounding environment, the information could be more completely obtained, thereby improving the safety and practicality of the video intercom system. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Single lens reflex indoor product photography skills
There were the following techniques for indoor DSLR photography: - ** Focus **: If there is a problem with focusing, you can first determine the shooting range, then place a rag doll, pillow and other reference items to focus, press the shutter and then place the product in the shooting position. You can also manually focus after determining the focus position. - ** In terms of reducing flashes and shadows **: - ** Distance between the character and the background **: Keep the character (if the product shooting involves the character) as far away from the white wall or the object behind it as possible. Maintain a certain space and distance, so that the flash shadow will be significantly weakened. - ** Setting selection **: Choose a bright background, such as using bright windows and doors under natural light as the background. You can also use existing lighting equipment such as table lamps to create a bright background for the subject. Choose an appropriate shooting angle so that the shadow of the flash disappears in the bright background. - ** camera position **: The camera should be positioned higher and more upright, so that the flash will be projected directly below the person's back, and a part of it will be blocked by the person being photographed, making it less obvious. Try not to shoot with a head-up or head-up camera position. To avoid portrait composition, because when shooting portrait, the camera had to rotate 90 degrees, and the flash was in the side position, which made it easier for the flash shadow to fall on one side of the character, leaving a thick black shadow on the background that was consistent with the outline of the character's side. When shooting banners, the flash light source was emitted from the top of the lens, and the projection was relatively weak. - ** Blocking the flash **: Due to the small indoor space and the close shooting distance, the use of the flash not only easily produces shadows, but also may make the face of the character pale. You can use white gauze, stockings, or even tissues to block the flash properly to make the flash source softer. When using it, stick gauze and other things outside the flash with tape (be careful not to block the viewfinder and focus hole). If the soft light effect of one layer is not ideal, you can add two or even three layers. However, the flash illumination will be reduced after blocking, so you should increase the exposure value appropriately. - ** Slow sync flash mode **: When shooting indoors with a flash, in addition to the flash light source, there is also natural light from the door and windows and indoor light. The latter two light sources are weak and cannot allow the subject to have enough exposure. You can use the slow sync flash mode, use the flash light source to illuminate the main character, and then use a longer shutter (1/15 - 1 second) to shoot other still objects in the room, using the original light in the room to weaken the shadow left by the flash. It is best to use a tripod when shooting. You can also use objects such as tables and chairs to fix the camera to prevent vibration. At the same time, the subject must maintain the original posture after the flash is lit until the shutter is closed. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to identify whether the camera lens is a legitimate product?
The following methods can be used to identify whether the camera lens is a legitimate product: 1. For Nikon lenses, you can call the Nikon 400 on the spot to check if the lens is a mainland license, production time, and other information. 2. Check the cleanliness of the front and rear lenses of the lens, remove the front and rear covers, and check if there is any fine dust inside the lens through the light. At the same time, do not let go of the inspection of the electronic contacts, which can reflect whether the lens has been installed on the body. Finally, carefully check the manual and the product serial number on the body to prevent the dealer from switching the package for sale. 3. You can go to the special dealers in the official website to ask them how to identify parallel goods. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>