What focal length lens should I use to take Taobao photos?
It was best to use a lens with a focal length of 35 - 50mm to take Taobao photos. This focal length was equivalent to the human eye's vision and would not cause any type difference. Read more exciting novels for free
the focal length of a camera lens
The focal length was the division of the focal length of the lens. It was generally divided into super wide angle, wide angle, standard, medium focal length, medium telephoto, telephoto, and super telephoto. Take a 35mm camera (135 camera) as an example: a lens with a focal length below 20mm is an ultra-wide-angle lens; a lens with a focal length of 21mm-40mm is a wide-angle lens; a lens with a focal length of 41mm-60mm is a standard lens; a lens with a focal length of 61mm-100mm is a medium-focal lens; a lens with a focal length of 101mm-180mm is a medium-long focal lens; a lens with a focal length of 180mm-300mm is a telephoto lens; A lens with a focal length of 301mm or above was a super telephoto lens. Different focal lengths had different characteristics and applicable scenes. For example, the ultra-wide angle lens had a wide angle of view, which was suitable for shooting large scenes such as scenery and architecture; the standard lens was close to the human eye's angle of view, with very little distortion, which was more suitable for documentary photography; the telephoto lens could achieve background blurring, compress space, and highlight the main body, but the scene was small, so it was difficult to blend the background with the main body well. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The focal length and characteristics of a photographic lens
The focal length was a measure of the concentration or dispersion of light in an optical system. The distance between the focal point and the center point of the mirror was the focal length, and the unit was "mm." If there was only one number on the lens, it was a fixed-focus lens. If there were two numbers, it was a zoom lens. Lenses with different focal lengths had different characteristics and functions: 1. ** Super wide-angle lens (focal length less than 24mm)**: - [Special characteristic: Large viewing angle] - [Function: It is suitable for shooting large scenes such as scenery and architecture. It can accommodate more elements in the picture, but the proportion of each element in the picture is small. At the same time, it is easy to produce distortion effects. It is difficult to control the effect in close-up shots.] 2. ** 24mm/28mm wide-angle lens **: - [Special characteristic: A wide viewing angle.] - [Function: Commonly used for shooting scenery, architecture, and other large scenes. It can also include many objects, but it may include unnecessary elements during composition, causing the picture to be messy.] 3. ** 35mm-85mm standard lens **: - [Special characteristic: The shooting effect is close to what the human eye can see. It looks natural.] - [Function: It is widely used in portrait shooting, with 35mm, 50mm, and 85mm being common focal lengths.] 4. ** 85mm lens (fixed-focus lens is outstanding in portrait photography)**: - [Special characteristics: Shooting angle of 28 degrees. With a large aperture, the background can be simplified, the character can be highlighted, and the background blurring effect is good. The distance from the whole body to the close-up is about 1.5 meters to 5 meters. The image quality is good, but the angle of view is fixed.] - [Effect: Excellent performance in portrait photography, regarded by many professional photographers as the king of focal length.] 5. ** Telephoto lens above 200mm **: - [Special characteristics: Narrow angle of view, can zoom in on distant objects, can perform a reduction process on the image to eliminate messy elements, has a strong sense of background compression, can make the main body and the background closer in perception, and the longer the focal length, the less obvious the face distortion effect. When shooting a portrait, the facial features will be slightly flattened.] - [Usage: Commonly used for shooting birds, sports events, and other long-distance subjects.] <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The relationship between the lens and the focal length
The focal length was a key characteristic of a photographic lens. The two were closely related and had many effects on the shooting: * * 1. Relationship between lens type and focal length ** 1. * * Wide-angle lens ** - A lens with a focal length of less than 35mm was a wide-angle lens. This type of lens had a wide angle of view and was suitable for shooting scenery, buildings, and other scenes that required a large angle of view. For example, when taking pictures of vast natural scenery or magnificent buildings, the wide-angle lens could bring more scenes into the picture. 2. * * Standard Shot ** - A lens with a focal length of about 50mm was considered a standard lens. Its angle of view was close to what the human eye could see, and it was often used for portraits and everyday photography. When using a standard lens to shoot a portrait, the proportions and space of the person were more natural. 3. * * Telephoto lens ** - Lenses with a focal length of more than 70mm were considered telephoto lenses and were suitable for long-distance shooting, such as wild animal photography and sports photography. A telephoto lens could make a distant subject look bigger in the picture, as if it was closing the distance between the photographer and the subject. * * 2. The effect of focal length on the lens shooting effect ** 1. * * Perspective * - The shorter the focal length, the wider the angle of view of the lens, allowing it to capture a wider scene. For example, when using a lens with a smaller focal length to shoot a city street, it could cover more street buildings and people. On the contrary, the longer the focal length, the narrower the field of view, which could make distant objects look closer. For example, when a telephoto lens was used to shoot wild animals, it could highlight the main body of the animal while blurring the background. 2. * * In terms of depth of field ** - A lens with a shorter focal length usually has a deeper depth of field, which means that a larger area of the picture will remain clear. This was very useful in landscape photography, such as using a wide-angle lens to shoot a large sea of flowers, from the flowers nearby to the mountains in the distance. The long focal length lens would produce a shallow depth of field, blurring the background and helping to highlight the subject. In portrait photography, the long focal length lens could clearly highlight the main character and blur out the messy background. 3. * * X-ray Transfiguration ** - Wide-angle lenses (short focal length) were prone to perspective distortion, making the object in the picture look farther or flatter than it actually was. For example, when shooting a person at close range with a wide-angle lens, the proportion of the facial features of the person may be out of balance, and the parts close to the lens (such as the nose and mouth) may appear larger than normal. The long focal length lens could better maintain the proportional relationship between the objects and reduce distortion. It was more suitable for shooting scenes that needed to accurately represent the shape of people or objects. * * 3. The relationship between the focal length indicator and the lens type ** - If the focal length label on the lens had two numbers, it meant that the lens was a zoom lens, and its focal length covered the focal length between the two numbers. For example, the 17 - 40mm logo meant that this was a zoom lens, and the focal length varied between 17mm and 40mm. If the focal length indicator on the lens only had one number, it meant that the lens was a fixed-focus lens. For example, a lens with a focal length of 50mm was a fixed-focus lens. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
90 focal length lens group photo
When taking group photos, a 90mm focal length lens was a more suitable choice. The standard lens had many advantages when taking group photos, such as the smallest distortion and the closest to the human eye's visual perception. When using a 120 medium format 6×7 camera to take a group photo of more than 500 people, using a 90mm lens could achieve better results. However, when using this focal length lens to take a group photo, one also had to consider other factors such as shooting distance, aperture, shooting time, queue position, etc., in order to take the ideal group photo. For example, it is recommended to choose soft natural light when shooting, such as 9 - 10 a.m. or 4 - 5 p.m.(It needs to be adjusted according to the season and regional differences). It is best to use a cloudy morning, and the direction of the light is best to be in the light. In terms of queue position, when there are more people, they can be arranged in a square array (for example, 50 - 100 people can be arranged in 4 - 5 rows). The height of the front and back rows should be reasonably arranged by chairs, stools, steps, etc. to avoid blocking. It is recommended to use a small aperture such as F11 or F16 (different cameras may have different aperture ranges). <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What kind of focal length lens do street models use?
Different focal lengths had different effects and uses when shooting models on the street. The 35mm and 50mm focal lengths were suitable for full-body shots, which could better interpret the background. The 50mm focal length was close to the human eye's vision and had the characteristic of " what you see is what you get ". The 85mm focal length was called the " Portrait Mirror Emperor ". The blurring effect outside the focal length was soft and beautiful, which was suitable for shooting half-body close-ups. The 105mm and 135mm focal lengths were also good choices for street portraits because of their longer focal lengths, but the long focal length would make the photographer and model far away, making communication inconvenient. The 70 - 200mm medium telephoto lens was the most commonly used lens for street shooting. Under the same aperture, the longer the focal length, the better the blurring effect. In addition, the focal length of a portrait was usually set between 50mm and 85mm because the 85mm lens basically did not distort the face and the image compression was strong. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Does the focal length of the flash have to be the same as the focal length of the lens? Why is it different?
The focal length of the flash and the lens did not need to be the same. On the one hand, from the function and principle of action, the focal length of the lens determined the size of the image, the size of the field of view, the depth of field, and the strength of the perspective of the image. It was the distance from the main point of the lens to the focal point. The main function of the focal length of the flash was to control the range and intensity of the light emitted by the flash. The smaller the focal length, the wider and more uniform the range of light, and the slower the decay. The larger the focal length, the narrower the range of light, the uneven and local brightness, and the faster the decay to the surroundings. On the other hand, from the point of view of creative intent and actual shooting situation, if you want the light to be concentrated or dispersed differently, you can set different focal lengths of the flash according to your own needs. For example, if you want to illuminate a deeper area of the scene instead of the entire scene for a special effect, you can manually set the focal length of the flash. And in some cases, even if the focal length of the lens changed, the automatic zooming function of the flash could be turned off and the focal length of the flash could be manually set according to the creative needs to obtain more creative freedom. However, when using a hot shoe flash, if the focal length of the flash and the focal length of the lens were not matched, such as the lens using a wide-angle focal length and the flash was not a wide-angle focal length, it might cause a dark corner in the shot. However, this did not mean that the two had to be the same, but it was a factor that needed to be considered when using specific equipment combinations. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to measure the focal length of a laser lens
The focal length of the laser lens was measured as follows: 1. ** Experimental measurement method ** - ** Roughly measure the focal length of the concave lens (uncertainty not calculated)**: clearly image an object in the distance (such as the scenery outside the window or a lit table lamp more than 5 meters away in the room) on the image screen. Move the lens back and forth, and measure the distance between the concave lens and the image screen with a steel ruler. This distance is the focal length of the lens. The reading is accurate to millimeters. It is not estimated below 1 mm. - ** Measuring the focal length of the concave lens by the two-time imaging method (estimated reading: 1/2 mm, uncertainty not calculated)**: Place the object screen and the image screen on the optical bench, so that the distance between the object screen and the image screen is greater than 4 times the focal length of the lens. The distance between the object screen and the image screen was kept constant, and the concave lens was moved. The positions of the concave lens corresponding to the magnified image and the reduced image were recorded clearly on the image screen, and the focal length of the concave lens was calculated after multiple measurements. - ** Measuring the focal length of a concave lens by auto-alignment ** - ** Manual reading (uncertainty limit 0.1mm, estimated reading 1/2 division value (mm))**: Put the light source, object screen, concave lens, and reflective mirror on the optical bench in turn, move the concave lens until a clear image is seen on the object screen (the method to determine that it is a self-aligned image depends on the specific experimental situation), and record the position of the object screen and the concave lens; then rotate the concave lens around the support by 180°, repeat the above measurement, and finally calculate the focal length and uncertainty of the concave lens. - ** Laser ranging (uncertainty limit 0.2mm, minimum indication value 1mm, no estimation)**: Similarly, place the light source, object screen, concave lens, and reflective mirror on the optical bench in order. Move the concave lens until a clear image appears on the object screen. Record the position of the object screen and the concave lens. Then rotate the concave lens 180° around the support and measure again to calculate the focal length. 2. ** Calculating using optical principles **: For an ideal thin lens, the formula can be used according to the curvature radius and refraction index of the lens.(f = \frac{(n -1) \times R}{2}\)(where <f> is the focal length,<n> is the refraction index of the lens material, and <R> is the radius of curvature of the lens). For thick lenses, the thickness of the lens and the curvature radius of the two surfaces need to be considered.(<frac{1}{f} = (n-1) (<frac{1}{R1} -<frac{1}{R2} -<frac{(n - 1)d}{nR1R2})>)>, where <R1> and <R2> are the curvatures of the two surfaces of the lens, and <d> is the thickness of the lens.) 3. ** Determined according to the characteristics of the laser resonant cavity **: In the laser system, the focal length of the laser resonant cavity is related to the mode radius and the optical wavelength of the laser crystal. The focal length of the thermal lens can be determined by measuring the output power of the laser, but this process involves the influence of the thermal effect of the laser on the parameters. 4. ** Use optical design software **: In modern optical design, professional optical design software can be used to help calculate the focal length. These software can simulate the path of light in the lens and accurately calculate the focal length. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Canon m50 longest focal length lens
Canon M50 lenses mentioned that 100 - 400mm or 200 - 400mm could be used for special needs (such as when shooting birds that required an ultra-long focal length lens). There was no mention of a longer focal length lens specifically for the M50, so the 200 - 400mm lens was currently the longest focal length lens known. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Small focal length lens sweeping the street
Small focal length lens (less than 35mm focal length) was a wide-angle lens. It was featured by a wide angle of view and could shoot large areas of scenery, but the distortion was large and easy to produce distortion effects. When sweeping the streets, this kind of lens could record the overall style of the street, including the surrounding buildings, many people, and rich scene elements. However, due to the distortion problem, the image of the character may be distorted when shooting, especially near the edge of the picture. Therefore, if a person was the main subject of the shot, one had to pay special attention to the composition and angle of the shot. Try to avoid the person from being at the edge of the picture. If you wanted to highlight the sense of space on the street, the lively atmosphere of the crowd, or the grandeur of the building, a small focal length lens was a good choice. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to exercise the focal length of the camera lens
You can practice using various focal lengths to understand the characteristics of each focal length of the lens, understand the angle and perspective relationship, and make use of the different depth of field of each focal length. For example, using a telescope (A lens with a focal length of more than 200mm) When shooting, you can feel that it has little sense of distance and has a compression effect.(85mm-135mm focal length lens) The perspective closest to the human eye, can accurately reflect the shape of the subject, can be used for portrait photography; Wide-angle lens (focal length below 35mm lens) can emphasize the sense of distance; Standard lens (focal length around 50mm lens) The shooting effect is extremely natural, without exaggeration. During the shooting process, he constantly summarized the differences in the effects of the images shot by different focal length lenses, which helped to train the focal length of the camera lens. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>