camera optical parameters
The optical parameters of the camera included the following aspects: 1. ** focal length **: This is a very important optical parameters of the lens. It refers to the distance from the main point of the lens to the focal point. It is an important performance indicator of the lens. The length of the focal length of the lens was inverse to the size of the image taken by the lens. That is, under the same object distance, the larger the focal length of the lens, the smaller the size of the image taken. Most industrial cameras use fixed-focus lenses in practical applications. Before choosing the focal length of the lens, you need to know the object distance of the on-site camera (the installation height of the camera lens from the surface of the measured object) and the field of view of the camera (the size of the characteristics of the measured object). In some applications involving the mixed inspection of objects at different heights, the use of a variable focal length lens would be considered. However, the variable focal length lens had two issues to consider: zooming speed and lens life. 2. ** Depth-of-field **: When the focal length of the lens is adjusted to a focal point, only the objects within a certain distance before and after the focal point are clearly visible. The objects outside this distance are blurred. This distance is the depth of field of the lens. 3. ** Pieces and resolution **: Pieces are the smallest unit of an image generated by the imaging chip, such as a 2-million-pel image. The resolution referred to the imaging ability of the CCD-or CMOS-chip. For example, the resolution of a 2-million-pel camera was 1626 x 1236, which meant that the camera had 1626 x 1236 rows in the X-axis direction. The total image taken was about 2 million pel. The detection accuracy could be simply evaluated by dividing the actual size of the image's X-axis by the number of X-axis dots. However, the final detection accuracy was affected by many factors, including the moving speed of the object being measured, light interference, the shape of the object, the contrast of the features, the computing power of the software, and so on. 4. ** Picture element size **: This is also an important optical parameters of the camera. 5. ** Target size of sensor **: It is the most concerned part of the camera's optical parameters. Read more exciting novels for free
The optical parameters on the lens
The following is some common optical parameters on the lens: 1. ** effective focal length (EFL)**: The distance from the center of the lens to the focal point. It could be divided into image focal length (the distance between the main surface of the image and the focal point of the image) and object focal length (the distance between the main surface of the object and the focal point of the object). If the focal length is too short, it will cause the field of view to be too large, causing distortion, difficulty in controlling the angle of the chief ray, low contrast, serious lens bending, difficulty in correcting the phase difference, and other problems. If the focal length is too long, the lens will be too long, which is not conducive to the miniaturized system. Moreover, the field of view is too small to meet the user's needs (FoV>60°). 2. ** Total length of lens (TL)**: It is divided into optical length (the distance between the first surface of the lens and the image surface) and mechanism length (the distance between the end of the lens barrel and the image surface). 3. ** Back focal length (BTL)**: The distance from the last side of the lens in the optical system to the image plane. 4. ** Front focal length (FFL)**: The distance from the first surface of the lens to the object surface in the optical system must be distinguished from the back focal length of the mechanism. 5. ** Mechanical back focal length (FTL/FFL)**: The distance from the last mechanical surface of the lens group to the image surface. 6. ** Field of View (FoV)**: The largest field of view that the camera can capture. It can be divided into diagonal field of view (FoV-D), horizontal field of view (FoV-H), and vertical field of view (FoV-V). The diagonal field of view is the largest, followed by the horizontal field of view, and the vertical field of view is the smallest. The so-called field of view refers to the diagonal field of view of the digital camera module. The size of the field of view was related to the focal length. Generally, the larger the field of view, the shorter the focal length. 7. ** Joules (F/NO.)**: It was the ratio of the effective focal length to the diameter of the pupil, which was used to determine the brightness of the lens. Under the premise of ensuring the same aperture, the shorter the focal length, the smaller the relative aperture should be. In general, the smaller the F/#, the larger the aperture. 8. Distortion: It is the off-axis phase difference. It is the height difference between the intersection point of the off-axis point and the main ray on the image plane and the ideal (paraxial-like) image plane. It is a function of the field of view and has nothing to do with the aperture. Distortion was divided into TV distortion and optical distortion. TV distortion was further divided into pillow type and cylinder type. Distortion is the image quality that users can easily feel. Different application scenarios have different requirements for distortion. For example, Optical-Distortion <3% is not easy to detect by the human eye, and the objective lens generally requires Optical-Distortion <2%. 9. ** relative illumination (Ri)**: The ratio of the central illumination to the peripheral illumination. If the contrast was too low, the center of the image would be bright and the surroundings would be dark (vignette phenomenon, commonly known as dark corners), which would also cause color distortion. The Ri is directly proportional to COS4 (semi-fov). Different semi-fov correspond to different theoretical values of the Ri. When the Ri<50%, the human eye can distinguish it. In serious cases, the four corners of the picture will be completely black. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The technical parameters of the optical lens
The main technical parameters of the optical lens were as follows: 1. ** effective focal length (EFL)**: The distance from the center of the lens to the focal point. It was further divided into image focal length (the distance between the main surface of the image and the focal point of the image) and object focal length (the distance between the main surface of the object and the focal point of the object). If the focal length is too short, the field of view will be too large, resulting in distortion, difficulty in controlling the main ray angle, low contrast, serious lens bending, difficulty in correcting the phase difference, and other problems, which is not conducive to the design; if the focal length is too long, the lens will be too long, which is not conducive to the miniaturized system. If the field of view is too small, it is difficult to meet the user's needs (FoV>60°). 2. ** Total length of lens (TL)**: It is divided into optical length (the distance between the first surface of the lens and the image surface) and mechanism length (the distance between the end of the lens barrel and the image surface). 3. ** Back focal length (BTL)**: The distance from the last side of the lens in the optical system to the image plane. 4. ** Front focal length (FFL)**: The distance from the first surface of the lens to the object surface in the optical system must be distinguished from the back focal length of the mechanism. 5. ** Mechanical back focal length (FTL/FFL)**: The distance from the last mechanical surface of the lens group to the image surface. 6. ** Field of view (FoV)**: refers to the largest field of view that the lens can capture. It can be divided into diagonal field of view (FoV-D), horizontal field of view (FoV-H), and vertical field of view (FoV-V). The diagonal field of view is the largest, followed by the horizontal field of view, and the vertical field of view is the smallest. The so-called field of view usually refers to the diagonal field of view of the digital camera module. 7. ** Joules (F/NO.)**: It is the ratio of the effective focal length to the diameter of the entrance pupil, which is used to determine the brightness of the lens. Under the premise of ensuring the same aperture, the shorter the focal length, the smaller the relative aperture should be. In general, the smaller the F/#, the larger the aperture. 8. ** Distortion **: It is the off-axis phase difference. It is the aberrations of the off-axis thin beam. It is the height difference between the intersection point of the off-axis point and the main ray on the image plane and the ideal (near axis) image plane. It is a function of the field of view and has nothing to do with the aperture. The primary distortion changes with the cubic power of the field of view (image height), and the percentage distortion increases with the square of the image height. The distortion varies with different fields of view, and the distortion changes are non-linear. It is only the distortion of the image and does not affect the clarity of the image. Distortion is divided into TV distortion and optical distortion. TV distortion is further divided into pillow type and cylinder type. Different application scenarios have different requirements for distortion. For example, Optical-Distortion <3% is not easy to detect by the human eye, and Optical-Distortion <2% is the distortion requirement of the photographic objective lens. 9. ** relative illumination (Ri)**: The ratio of the central illumination to the peripheral illumination. If the contrast was too low, the center of the image would be bright and the surroundings would be dark (vignette phenomenon, commonly known as dark corners), which would also cause color distortion. The Ri is directly proportional to COS4 (semi-fov). Different semi-fov values correspond to different theoretical values of the Ri. When the Ri<50%, the human eye can distinguish it. In serious cases, the four corners of the picture will be completely black. 10. ** resolution **: It can be defined as the number of pairs of black and white stripes that can be distinguished in millimeters when the lens is used to observe the black-and-white grid pattern. When selecting a lens, the lens resolution is usually required to be slightly higher than the resolution of the picture element. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The parameters of the camera
The main parameters of the camera lens were as follows: - Aperture: controls the amount of light that enters the lens. The smaller the aperture, the greater the amount of light that enters the lens, and the more obvious the background blurring effect. For example, in a dark environment, a large aperture could allow more light to enter the camera and take a bright photo. At the same time, it could highlight the subject and blur the background. - ** Focus **: determines the angle of view and magnifying power of the lens. The short focal length lens had a wide angle of view and was suitable for shooting large scenes such as landscapes. The long focal length lens had a narrow angle of view and could zoom in on distant objects. It was often used to shoot portraits, close-ups, or sports events that needed to be zoomed in. - ** Shutter Speed **: The length of time the shutter is opened. A fast shutter speed could freeze instantaneous movements, which was suitable for shooting moving objects, such as fast running athletes. A slow shutter speed could capture the trajectory of the object's movement, such as shooting a smooth effect when shooting water. However, a slow shutter speed needed to be used with a tripod to prevent blurring caused by hand shaking. - [Depth-of-field]: It refers to the range of clear images before and after the focal point. A large aperture would cause the depth of field to become shallow, that is, the clear range before and after the focus was small; a small aperture would cause the depth of field to be large, and the clear range before and after the focus would be wide. - ** Light sensitivity (USB)**: It indicates the sensitivity of the camera to light. The higher the value, the more sensitive the camera was to light. In a dim environment, the camera could increase the brightness by raising the value, but an overly high value would cause noise and affect the image quality. - ** White Balance **: Adjusts the camera to ensure that white objects appear white under different lighting conditions. Automatic white balance (AWB) for daily shooting can basically meet the needs, but it can be manually controlled in special scenes or when you want to change the image effect, such as using the built-in scene mode, manually adjusting the K value, etc. - ** Distortion **: Different types of lenses may have different degrees of distortion. For example, wide-angle lenses may produce barrel distortion, and telephoto lenses may produce pincushion-shaped distortion. This was something to take note of when shooting objects that required strict shapes such as buildings. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The parameters of the camera
There were many parameters for the camera lens. The following were some common parameters: 1. ** Focus **: It determines the degree of zooming of the lens. A longer focal length was used for long-distance shooting. For example, a telephoto lens could be used to shoot long-distance topics such as sports competitions, wild animals, aircraft, etc., and it could also enhance the background blurring effect. A shorter focal length was used for wide-angle shooting, such as wide-angle lenses for landscape photography, architectural photography, and crowded indoor spaces. 2. ** Aperture **: For example, the main camera of the Vivo X200 Pro is equipped with a large aperture of f/1.57, which helps to take brighter and clearer photos in dark environments. Its periscope telephoto lens has an aperture of f/2.67, which can ensure the clarity and details of the picture when shooting telephoto. The size of the aperture affected the amount of light entering, depth of field, and so on. 3. ** Pieces **: It is one of the important indicators to measure the quality of the camera. For example, the main camera of the Vivo X200 Pro is expected to use a 50-million-pel large sensor, and the periscope telephoto lens is equipped with a 200-million-pel periscope telephoto lens. 4. ** Photosensor **: For example, the sensor of the HD - 3000 camera is a LCD; the main camera of the Vivo X200 Pro has a 1/1.28-inch sensor, and the periscope telephoto lens has a 1/1.4-inch base. 5. ** View angle **: For example, the helmet camera lens is a 3.7mm pinhole lens with a 90-degree view angle. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Diving camera parameters
The following are some of the parameters of the diving camera: - Diving goggles digital camera: It is equipped with a 5-million-pel camera and is powered by two AAA-grade batteries. It can take still photos with a resolution of up to 2560×1920. It has 16-MB flash memory on board. You can download photos and videos by connecting it to the computer's USB port. - Olympus Tough TL- 6:1/2.3-inch sensor, 12-million-resolution, 25 - 100mm f/2 - 4.9 lens, 15m waterproof,-10 ° C frost resistance, 2.1m shockproof, 3-inch screen, 4K video support, 4K, 4K, GPS support, intermediate user level. - D.J. Osmo Action 3 Diving Set: <br><br> The sensor is a <br><br><br> LCD, measuring 1/1.7 inch, with 12 million effective pixel-count. The electronic shutter speed is 1/8000 to 30 seconds for photography, and 1/8000 seconds for video recording.<br> The anti-shake performance is electronic anti-shake. The image format is 4000×3000, and the video format supports 4K/2.7K/1080p. The image and video recording range is 100 to 12800. It is waterproof to 16 meters. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
English camera parameters
The following are some common English camera parameters and their meanings: 1. ** Metering Mode **: It can be divided into Spot Metering, Matrix Metering, and Center Metering. It is used to adjust the environmental effects and lighting modes according to different environments. 2. ** Iso-Mode **: Iso-level is the sensitivity of the film. The value can be adjusted (automatically or manually according to the environment). The higher the sensitivity, the rougher the film will be. The magnifying effect is average. The light sensitivity will be different at different times (such as early morning, noon, and sunset), so it needs to be adjusted according to the environment. 3. ** Shutter Speed Mode **: S represents Shutter Speed. The shutter speed can be adjusted. The longer the shutter time, the longer the time taken to take a photo. The lower the shutter speed (that is, the longer the shutter is open), the longer the exposure time. It can be used to shoot moving objects. 4. ** SUV Mode **: SUV refers to exposure compensation. When the light is too bright during the day, the photo can be dimmed to prevent excessive exposure from affecting the picture. For every 1.0 increase in the RV exposure value, the light would double. When the photo was too bright, the exposure value would be reduced by 1.0, and the light would be reduced by one. The shutter speed was the exposure time, which was an important factor in the photo. 5. ** AF-mode **: Focus mode, also known as "auto-focus." It was divided into two types, active and passive. The infrared rays sent by the camera tracked objects or people, and the distance of the current object and the subject could be determined. Ordinary mobile phones could achieve these two focus modes. 6. **AWB Mode **: White Balance Mode. Simply put, a piece of white paper will appear in different colors under different light. White Balance will affect the color tone of the entire photo. You can adjust the cool color tone on cloudy days and the warm color tone at sunset. In the parameters related to video shooting: 1. ** RPM (Rate-Picture- Bit)**: Modifies the rate of the captured video. There are two settings, high and low, which determine the clarity of the picture and the file size of the captured video. In monocular camera calibrations, there were: 1. ** Internal Parameters **: 10 camera internal parameters are only related to the camera, including 5 internal matrix parameters K (can be regarded as 4 parameters fx, fy, u0, v0, where fx = f/dx, fy = f/dy, where f is the focal length, dx, dy are the length and width of the point, u0, v0 are the coordinates of the main point in the image coordinate system) and 5 distortion parameters D (k1, k2, k3, p1, p2 are the radius distortion coefficient). 2. ** External parameters **: The relevant parameters from the world coordinate system to the camera coordinate system (used to describe the position of the camera and other information. In the process of camera calibration-related information, the camera's position information and internal parameters are obtained from the spatial points and their corresponding pixel-points). <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Firework parameters of the camera
When shooting fireworks, the camera parameters were set as follows: - * * Shutter Speed (exposure time)**: - If you want to record the fireworks display process, about 3 seconds can perfectly record the temporary fireworks display process; when there are many fireworks in the same place, the best exposure time is within 7 seconds, and the image may be overexposed beyond 7 seconds; if there are more fireworks and the fireworks are concentrated, about 4 seconds is more suitable; if you want to completely record the trajectory of the fireworks from the lift to the release, about 7 seconds is enough. - It could also be controlled within 10 seconds of hearing the "bang" of the fireworks. If you wanted to capture fireworks for a period of time, you could extend the time. You could also control the shutter through the B-door to achieve the required image exposure time. - There were also some parameters for reference, such as shutter speed of 2.80 seconds, 6.30 seconds, 14 seconds, and other parameters for different effects.(Different shutter speeds need to be adjusted with aperture, IQ, and other parameters.) - The shutter speed was 1/20S-1/50S if one wanted to shoot fireworks, and 1/100S or above if one wanted to shoot stars. - * * Aperture **: - When shooting fireworks without blurring the background, the aperture could be controlled in the range of f/8-f/20. There were also examples of aperture settings for different effects such as f11 and f8. When the environment was too dark, the aperture could be set to a larger aperture. When the environment was relatively bright, the aperture could be set to a smaller aperture. If you wanted to shoot fireworks, the aperture was generally between F5-F9. If you wanted to shoot stars, use a small aperture, such as F10 or smaller. - * * USB (Light Speed)**: - The settings were based on the shooting environment. For example, if you wanted to shoot the effect of fireworks, the USB was usually 500. In different environments, the USB needed to be adjusted according to the shutter speed and aperture to achieve the ideal shooting effect. - * * Focus **: There are examples of shooting effects under different focal lengths such as 16mm and 35mm. You can choose according to your actual needs. - * * Focus **: After finding the shooting position and setting up the camera, you must first focus. Since the night sky is almost pure black, there is little information, so you need to pay attention to the focus operation. - * * White balance **: If you adjust the white balance to 2900K (only for reference), you can adjust it according to the actual situation. In addition, for the iPhone, you can turn on the camera in the settings, click to record a video, choose 4K60, turn on HVR, turn off the automatic FPS to lock a frame number, lock the white balance, and click on the main body of the fireworks to lower the brightness to a suitable position when shooting fireworks. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Character camera parameters
The camera can use the following settings when shooting people in the studio: 1. ** Shooting Mode **: Choose manual mode (M). 2. ** Aperture value **: Usually, you can choose f11 or f15, so that the subject is in the clear range. Of course, you can also adjust the aperture according to the specific effect you want to achieve, and control the background blurring or clarity through the aperture. 3. ** Light sensitivity (USB)**: The USB value can be set to 100 to meet the needs of the camera while reducing the impact of noise on the quality of the photo. 4. ** exposure compensation **: can be set to-0.5E. In addition, different cameras and shooting scenes may need to fine-tune these parameters. At the same time, the photographer's shooting skills, composition, and lighting will also have an important impact on the quality of portrait photos. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Single camera parameters
The parameters of a monocular camera included the following aspects: 1. ** Internal camera reference ** - ** Focus **: There are two ways to express it. One is the ratio of the ideal focal length to the camera's cell size.(f/dx f/dy), the ideal focal length in the lens system can pass through the object distance D (the distance from the object to the lens when it is in focus), the focal length of the lens, f, according to the lens formula,(1/f = 1/d + 1/D, d is the image distance, the ideal focal length). If it is not convenient to measure D, you can also measure the value of D/d (find an object with a known length and take the length of the object in the camera image when it is in focus. D/d = the actual length of the object/(the length of the image * the size of the image)), and then combine the above formula and f to find the size of D to obtain the ideal focal length. For ordinary industrial camera lenses, the focal length of the industrial lens could not be directly used to replace the ideal focal length. - ** Center of the camera's image (u0, v0)**: Usually half of the camera's resolution. For example, if the image's size is 800*600, the center of the image is (400,300). - ** Distortion factor (k1k2k3p1p2)**: For ordinary industrial camera lenses, the distortion factor is usually not very large. 2. ** Dimension of the sensor **: For example, a 1/3 inch sensor, the diagonal size is about 1/3 inch = 8.47mm, and the common width and height are about 4.8mm (width) x 3.6mm (height). 3. ** Image resolution **: For example, 1920x1080 (1080p). 4. ** Other parameters related to imaging (will be involved in different scenarios)** - ** The main points involved in monocular ranging (Cx and Cy)**: Because the installation of the imaging device in actual production cannot reach the accuracy of the millimeter level, the optical axis of the lens and the center of the sensor chip are not in the same line, so these two parameters are introduced to correct the hardware offset. - ** The parameters involved in the monocular camera imaging principle **: The monocular camera imaging principle includes the lens imaging principle and the photographic imaging principle. The lens imaging principle involves the focal length f in the small hole imaging model, the intersection point of the optical axis and the imaging plane (the main point), and other concepts. In the actual camera model, it may also involve fx and fy (because a single pel is rectangular instead of square on a low-cost imaging device). <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Star camera parameters
When shooting stars, the camera parameters were set as follows: - ** Focus mode **: Use manual focus MT more often. First, he switched the focus mode to manual focus, then opened the aperture, increased the exposure time, and increased the IQ. Then, he turned on the real-time display shooting, selected the magnifying glass button on the camera, magnified the stars in the night sky, and then adjusted the focus ring to achieve precise focus. - ** exposure parameters (usually choose manual exposure M)**: - ** Aperture **: You can choose a large aperture, such as F4, F5.6, f/2.8, etc. - ** Shutter Speed **: Choose 20 - 30 seconds. It is not recommended to exceed 30 seconds. Otherwise, it is easy to form a star orbit. - ** Light sensitivity **: It is the key to controlling exposure. Generally, it needs to be above 1600. When the aperture and shutter speed brought less exposure, the USB could be adjusted to 3200 - 6400, but a high USB had a requirement on the camera's performance, and high-end cameras could generally meet it. - ** White Balance **: It is recommended to take a photo with automatic white balance first, and then lower the color temperature by 500 - 1000K to create a better image atmosphere. - ** ExposureCompensationRV **: It can be slightly increased according to the shooting environment, or it can be left unset. - ** Light sensitivity **: Can be set between 800 - 3200, for example, 1250. In addition, shooting stars also had requirements for cameras, lenses, tripods, and other equipment: - ** Cameras **: Cameras with high sensitivity are more suitable. Full-frame cameras are the first choice for shooting stars. Entry-level DSLR cameras can also be used, but the high-sensitivity performance is not as good as full-frame cameras. You may need to increase the exposure time to make up for it. - ** Lenses **: It would be best if it was a wide-angle lens with a large aperture. The large aperture could increase the exposure of the picture under the same exposure time, making the stars bigger, and the wide-angle end could make the shooting of the Milky Way and other pictures have a visual impact. - ** Tripod **: Because shooting stars generally requires a long exposure time (usually within 30 seconds), you need a stable tripod. When using it, pay attention to the camera's anti-shake, such as turning off the lens anti-shake, turning on real-time display shooting, using the shutter release, etc. The equator could maintain the relative position of the camera and the starry sky background, but it was inconvenient to carry and expensive, so it was not a necessity. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>