How many suitable lenses should be chosen for the focal length?
The focal length of the lens depended on the shooting requirements: 1. ** Portrait Shooting **: - For close-up portraits, 85mm was a better choice because the facial features displayed at this focal length were more natural. Compared to wide-angle lenses, it would not cause the facial features of the character to be distorted, and compared to telephoto lenses, it could make the facial features of the character more three-dimensional. However, when taking a close-up portrait with a focal length of 17mm, the object closer to the lens would be magnified due to the wide angle. It was easy to cause the parts close to the lens such as the mouth, nose, and arms to be deformed, and the ratio of the character to the background would be more exaggerated. 2. ** Daily Shooting (The angle of view is similar to the human eye)**: - The focal length of a standard focal length lens was about 50mm. The angle of view of this type of lens was similar to that of the human eye. It was small in size and had a large aperture. The technology was usually more mature and the sales volume was high. 3. ** Zooming lens requirements (requires flexible focal length adjustment)**: - The focal length of a zoom lens was generally between 28 - 200mm. It could continuously change the focal length. One lens could replace a variety of lenses with different focal lengths, and it could continuously change the scene by continuously changing the focal length, forming the effect of pushing and pulling the lens. Common zoom lenses were 12mm-75mm (6x), 10mm-150mm (15x), 9.5mm -143mm (15x), and so on. If the focal length marked on the lens has two numbers (such as 24 - 70mm), it means that this is a zoom lens, and its focal length can be adjusted between these two numbers; if there is only one number (such as 50mm), it is a fixed-focus lens, and it can only be fixed at this focal length. 4. ** Wide-angle effect (requires a wider angle of view and more framing elements)**: - The smaller the number, the shorter the focal length, the wider the angle of view, the wider the viewing range, and the more elements the picture contained. For example, a focal length indicator such as 17 - 40mm indicated that this was a zoom lens. At the 17mm end, a wider angle of view could be obtained. It was suitable for scenes that required a large angle of view and multiple elements, but the proportion of each element was small. Read more exciting novels for free
How to choose the best focal length for industrial lenses
Choosing the best focal length for industrial lenses required a combination of many factors: 1. ** Consider the size of the object to be measured and the required magnification **: - If you want to shoot smaller objects and need a higher magnification, you should choose a lens with a longer focal length. For example, when shooting fine objects such as tiny electronic components, a longer focal length helped to magnify the object so that the details could be observed more clearly. - If you need to shoot a larger object or a wider field of view, it is suitable to choose a lens with a shorter focal length. For example, when shooting the overall appearance of large industrial equipment, a short focal length could cover a wider field of view. 2. ** Combining working distance and field of vision **: - Given the size of the camera's CCTV, the working distance (WD), and the field of view (FoV), the focal length of the required lens can be calculated according to the formula: focal length f = {working distance/long side (or short side) of the field of view}× long side (or short side) of the CCTV. When the ratio of the long side and the short side of the field of view is less than 4:3, the short side is used for calculation; when it is greater than 4:3, the long side is used for calculation; when it is equal to 4:3, both the long side and the short side can be calculated. 3. ** Considering the size of the camera's CCD-sensor **: - Because there was a standard for the size of the CCD-chip, different sizes of CCD-chips with different focal lengths of the lens would produce different imaging effects. The maximum CCD-size that the lens could support should be greater than or equal to the size of the CCD-chip of the camera. 4. ** Take into consideration the imaging effect **: - The resolution of the same camera would be different if different focal lengths were used. The appropriate focal length should be selected according to the requirements of the imaging resolution to ensure a clear and high-quality image. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Which focal length lens is suitable for novices?
For beginners, the following focal lengths were more suitable: 1. **18 - 55mm or 18 - 200mm zoom lens **: This type of lens is an entry-level camera lens. Among them, the 18 - 200mm lens was known as "one lens can travel the world." The focal length covered from wide angle to telephoto. Whether it was shooting scenery or people, it could be easily dealt with, providing more choices for beginners. 2. ** 50mm F/1.8 lens **: This lens is suitable for beginners to take portraits. Compared to the 18 - 55 lens, its advantage is that the aperture is large enough. It can have a very good blurring effect when shooting portraits. It is also very good for shooting food. 3. ** Mid focal length zoom lens **: 24 - 70mm, 24 - 105mm, 18 - 135mm, etc. are all good choices. They are convenient and have a wide shooting range, from portraits to landscapes. 4. ** Phone focal length **: If you use a phone to shoot, you can use the wide-angle focal length for the door, the surround focal length for the environment, the macro focal length for the product, and the double focal length for the character. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What kind of video is the 85 focal length lens suitable for?
The 85mm focal length lens was suitable for shooting many types of videos. It performed well in portrait video shooting. Due to the minimal facial distortion of the main subject and the ability to effectively separate the main subject from the background, it could shoot videos with good background blurring effects and prominent characters. If one were to take a close-up shot of a person's face, such as a person's expression, makeup, and other details, the 85mm lens could capture a beautiful and compact picture at a reasonable distance. In landscape video shooting, the 85mm fixed-focus lens could divide the complex landscape into small angle structures, making the landscape look more exquisite. For example, when shooting garden landscapes, it could show the exquisite beauty of Jiangnan gardens. It was also more suitable for cultural video shooting. For example, when shooting a chaotic and busy space such as the backstage of an opera performance, it was easy to find a unique aesthetic of the picture. Through the large aperture, it could also cut out the layering of the picture and create an artistic space. When shooting a cultural landscape video that included characters, it could prompt the photographer to think about how to better integrate the characters into the picture, create a sense of visual harmony, and create a hazy effect of the environment. It could weaken the main body to leave space for the audience to associate, and convey the atmosphere and emotions. In addition, large aperture lenses such as 85mm f/1.4 could achieve a large blurring effect when shooting short films. If the lens was equipped with an IS Image Stabilizer, it could help capture clear images in dim scenes. The USM ultrasonic motor also provided a quiet and rapid autofocus experience, which helped to improve the overall effect of video shooting. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What kind of camera is the 85 focal length lens suitable for
The 85mm focal length lens was suitable for shooting portraits, and there were excellent models that were suitable for many camera brands. For example, the Nikon Z85F1.2 camera had a suitable lens. Canon cameras also had lenses like the RF85mmF1.2LUSM, which used nine sets of 13 optical structures, including one piece of KD ultra-low dispersion lens, one piece of polished aspheric lens, and one piece of PR optical element. It had nine circular aperture blades, the closest focusing distance was 0.85 meters, and the maximum magnification was about 0.12 times. It used a ring-shaped ultrasonic focusing drive system. The filter aperture was 82mm, the maximum diameter and length were about 103.2×117.3 mm, and the lens weighed 1195 grams. It was priced at 17899 yuan. The F1.2's maximum aperture could bring about a relatively small depth of field and a large and beautiful blurring effect. It could highlight people very well in portrait photography. The camera also had an 85mm f/1.4 DG HSM Art lens, which was a medium-telephoto fixed-focus lens with built-in anti-shake functions. The 85mmF1.8 lens in Pantheon's full-frame fixed-focus F1.8 series used eight sets of nine lenses (two ED lenses) to provide a soft blurring effect. Although the Fuji camera did not have a direct 85mm focal length lens, the XF56mm F1.2RQR lens had a focal length of 85mm in the 35mm format, which could be used for portrait shooting and other purposes. The 85mm focal length lens of different camera brands could play the advantages of being suitable for shooting portraits and other scenes on their respective camera bodies. The specific choice depended on the photographer's comprehensive consideration of the camera brand, performance, budget, and many other aspects. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What kind of focal length lenses do I need to match for beginner photography?
For beginners, the following focal lengths were more suitable: - Super wide-angle lens (focal length below 24mm): It has a large visual range and is suitable for shooting buildings and landscapes. It can shoot a small space in a small space. - Standard wide-angle lens (24mm-28mm): Mainly used for shooting scenery. - General wide-angle lens (35mm): It is called the Humanistic Eye, suitable for taking cultural photos, and can better reflect the relationship between the subject and the background environment. - Standard lens (50mm): It is mostly used for shooting humanities and portraits. It has a perspective effect similar to the human eye and a good background blurring effect. - Portrait lens (85mm): It has a good background blurring effect, suitable for close-up shots, and can maintain an appropriate communication distance with the model. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
objective focal length
The focal length of an objective lens is an important factor in an optical system. There were many methods to measure the focal length of an objective lens. The fixed-focal length collimator method had a large measurement range and high accuracy. The relative error was generally less than 1%. It was a commonly used measurement method. In a telescope, the multiplying power was equal to the focal length of the objective lens divided by the focal length of the eyepieces. In terms of aperture, the F value was the ratio of the focal length of the objective lens (f) to the perimeter of the entrance pupil (D). Different types of telescopes or instruments had different focal length values of the objective lens. For example, the focal length of an astronomical telescope was 400mm, and the focal length of the objective lens of the ZWJ - 851 Collimator was 200mm. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
On the application of focal length
In the field of photography, focal length was widely used. When shooting portraits, different focal lengths would produce different effects. For example, a focal length of 85mm was a better choice for close-up portraits, which could show a more natural facial features ratio. When shooting close-up portraits with a focal length of 17mm (a wide-angle focal length), the parts close to the lens such as the mouth, nose, and arms would be magnified, easily deformed, and the ratio of the character to the background would be exaggerated. As the focal length increased, the ratio of the character to the background would become more natural, the distance between the five facial features would be shortened, and the face would become flatter. The hairstyle would look thicker, and the face would not be so sharp. For the lens label, if the focal length label on the lens had two numbers (such as 17 - 40mm), it meant that it was a zoom lens, covering the focal length from 17mm to 40mm; if there was only one number (such as 50mm), it was a fixed-focus lens. The smaller the number, the shorter the focal length, the wider the angle of view, and the wider the viewing range. The picture could accommodate more elements but the proportion of each element was small. The larger the number, the longer the focal length, the narrower the angle of view, and the narrower the viewing range. The picture could accommodate fewer elements but the proportion of each element was larger. In some simple self-made microscopes (such as the glue stick microscope with an adjusted focal length), the focal length needed to be adjusted to observe the object (such as garlic film). <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What focal length lens is suitable for taking jewelry photos?
When buying the first macro lens to shoot jewelry, it is recommended to choose a lens with a focal length of 60mm, which can make the magnification 0.5 times. If you have the financial ability, you can buy a macro lens that can shoot at a 1:1 ratio. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Normal focal length of glasses
Normal glasses included short-sighted glasses and far-sighted glasses (presbyopic glasses). The focal length was related to the degree of the glasses. For short-sighted glasses, the degree and focal length were in an inverse relationship, that is, the shorter the focal length, the higher the degree. For long-sighted glasses (presbyopic glasses), the degree of the concave lens (far-sighted lens) was positive, and there was a similar relationship between the degree and focal length. To be specific, the power of the lens was equal to 100 divided by the focal length (in meters). For example, a 100-degree spectacles would have a focal length of 1 meter. However, it was not clear whether "normal glasses" were short-sighted or farsighted, so it was impossible to determine a specific focal length value. This was because different degrees of glasses had different focal lengths. From correcting mild vision problems to high vision problems, the focal length would vary greatly. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Staircase camera focal length
For a relatively narrow environment such as stairs, a 2.8mm focal length camera could generally be used. Its field of view was larger and the range that could be seen was the largest. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>