How to adjust the aperture of a lens with good dispersion control
The aperture of a lens with good dispersion control was adjusted in a similar way to other lenses. There were blades around the aperture of the lens. Through these blades, the aperture could be opened and closed to control the amount of light entering. Only the light that passed through the aperture could continue to move forward. Some lenses might have special designs. For example, some lenses had two paddles at the end of the lens, which needed to be stuck with the body bayonet or the structure on the transfer ring before the aperture could be adjusted. In the single-lens state, the aperture was always open. There were also lenses whose control ring function could be customized. The aperture adjustment function could be assigned to the control ring of the lens, and the aperture could be adjusted through the control ring. However, in general, the dispersion control effect of the lens was not directly related to the aperture adjustment method. The two were two different characteristics of the lens. Read more exciting novels for free
Nikon lens dispersion evaluation
Among Nikon lenses, some lenses that used ED (Extra-low Dispersion) lenses performed better in terms of dispersion control. For example, the Nikon Z14 - 24mm F2.8S had luxurious materials, excellent distortion, dispersion, and ghost control; the Nikon Z100 - 400mm F4.5 - 5.6 VR S lens had excellent anti-glare, dispersion, and dark angle control; and the Nikon Z-mount 100-micro lens had heaven-defying dispersion performance. However, even though Gold Wide-angle, Silver Wide-angle, Small Cannon, and 28 - 70 Old Mirror Emperor had many ED lenses, they still often had purple edges, indicating that the dispersion control was not perfect. In general, different Nikon lenses had different performances in terms of dispersion control based on their positioning, price, and technical application. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What are the problems with lens dispersion and glare?
The lens dispersion was caused by the lens not focusing light of different frequencies into the same focal plane, or the degree of amplification of light of different frequencies was different. It could be divided into "vertical aberrations" and "horizontal aberrations." The lens showed that the degree of dispersion of the glass would lead to different degrees of color aberrations. Because the camera lens used white light to form an image, and white light was composed of different wave-length visible light. Different wave-length visible light passed through the glass at different speeds and had different refraction index. After the light passed through the lens, it was similar to a prismatic mirror effect. Different wave-length light could not be focused at the same focal point, forming dispersion (purple edge phenomenon) on the image. In theory, it could happen in the center and edge of the image, but the optical path at the edge was long, and the dispersion was more obvious. The short wave-length had high refraction index, and purple was sensitive to color difference. The purple edge usually spread from the inside to the outside, and the optical path of the telephoto lens was long, so the dispersion phenomenon was easy to see. The lens glare was caused by the light spreading and reflecting inside the lens. The camera lens was composed of many individual lens units. When the light passed through, most of it passed through directly, and some of it was reflected back by the lens surface. This internal reflection of light reached the sensor and formed a lens glare. It was manifested by the appearance of light spots and fog in the photo, which would reduce the contrast and saturation of the photo. The glare of a zoom lens was more serious than that of a fixed-focus lens because it had more lens units, so the light spread and reflected more. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The difference between lens glare and dispersion
Glare and dispersion are two different phenomena in lens optical aberrations. The lens glare was caused by the light spreading and reflecting inside the lens. The camera lens was composed of multiple individual lens units. When light passed through these lenses, most of it would pass through directly, and some of the light would be reflected back by the lens surface. A portion of the reflected light inside the lens would eventually reach the sensor, forming a light spot, which was the lens glare. Glare would cause light spots and fog to appear in the photo, which would reduce the contrast and saturation of the photo. Dispersion refers to the phenomenon that light of different colors (different frequencies) cannot be focused on the same point after passing through a lens. This was because different colors of light had different degrees of refraction in the lens, resulting in differences in their positions on the image plane. In terms of imaging, it might appear as colored edges at the edges of the image, affecting the clarity and color reproduction of the image. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to adjust the aperture shutter
Aperture, shutter, and USB settings needed to be considered based on the scene, the subject, and the desired effect. First, the setting of the USB. If there is enough light, in order to maintain the quality of the photo, you can set the USB to a lower value, such as 100, 125, 200; if the environment is dark, you can increase the USB to 800, 1600, 3200, but the higher the USB, the more obvious the noise, so you should use a high USB with caution. Then, he considered the aperture. The size of the aperture affected the amount of light entering and the depth of field. A large aperture (such as f/1.4) was suitable for use in dim light and could produce a shallow depth of field effect (commonly used for portrait photography); a small aperture (such as f/8 - f/11) was suitable for use when there was sufficient light to make more scenes clear (commonly used for landscape photography). Then the shutter. The shutter speed affected the motion blur and the amount of light that entered. A high-speed shutter (such as 1/1000s) was suitable for shooting high-speed moving objects. It could freeze the moment, but the amount of light entering was small. A slow shutter (such as 1/50s) had a lot of light entering. It was suitable for shooting scenes that required motion blur effects. However, if the shutter was too slow, the hand-held shooting might cause the picture to be blurred due to hand shake (when the shutter was lower than the safety shutter). In this case, the shutter speed could be increased by increasing the aperture or enlarging the aperture. When adjusting these three parameters, one had to pay attention to the relationship between the three to achieve the appropriate exposure. For example, under the condition that the exposure value is constant and the shutter speed is constant, the aperture value increases, and the USB needs to be increased; the aperture value is constant, and the shutter speed increases, and the USB needs to be increased; the USB value is constant, and the aperture value increases, and the shutter speed needs to be decreased. And in actual shooting, you can start from the semi-automatic mode (aperture priority or shutter priority) to practice, gradually master the deployment of the three, and finally realize the proficiency of setting these three parameters in manual mode according to different shooting needs. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What does the dispersion of the single-lens reflex lens mean?
Dispersion in an SLR lens referred to the fact that the lens glass had a different refraction index for different colors of light, resulting in different colors of light being unable to be accurately focused, and different colors of light would appear in the edge area of the image. Major lens manufacturers and optical researchers put in a lot of effort to introduce Canon, Nikon, Tamron and other low-dispersion glasses. Canon also made fluorite lenses to solve the dispersion problem. When the lens was not made of low-dispersion glass, the dispersion problem could also be solved by avoiding backlighting, reducing the aperture, and post-adjustment. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What is the effect of the filter that controls the lens dispersion?
In photography, the filter that could control the lens 'dispersion was mainly an ultra-low dispersion filter. Although there was no comprehensive explanation of the function of such a filter, the function of the filter was usually to improve the effect of the image. Just like how the CPL filter could reduce glare and increase saturation, the ND filter could extend exposure time, and the GND filter could control the gradual change of strong light and reduce vignette, the ultra-low dispersion filter could control the dispersion phenomenon to prevent the image from color dispersion and other problems caused by dispersion, thereby improving the image reproduction, making the image more in line with the shooting expectations in terms of color and clarity. It played an important role in photography scenes that required high color accuracy and picture purity. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Large aperture lens photography
Large aperture lenses could produce many unique effects in photography. In portrait photography, a large aperture lens could create a shallow depth of field effect, making the subject clear and the background blurred. For example, the lens of Nikon 105mmF1.4E and Canon 85mmF1.2L II USM could soften the background when shooting portraits, making the characters more prominent. At the same time, the out-of-focus image could show a soft light spot effect. In night photography, a large aperture helped to increase the amount of light entering in a dimly lit environment. For example, when shooting a portrait at night, a large aperture lens could ensure a safe shutter speed while increasing the overall brightness of the picture. For example, when the Sony-ZVE 10 was matched with a 0.95 large aperture lens, the ideal effect could be obtained by setting parameters such as 50mm 160s, f0/95, and Iso160. In terms of flower photography and skit photography, a large aperture lens was also a good choice. For example, when shooting a sketch with a Zeiss 75mm f1.5, the blurred effect brought by the large aperture could make the subject more prominent and have a unique layering. However, when shooting with a large aperture lens, for some lenses, the maximum aperture may have problems such as poor image quality, bi-linear, purple edges, etc. For example, 35mm f/1.4L II would have obvious purple edges when using the maximum aperture, while higher quality lenses such as 85mm f1.2, 135mm f2 and other maximum apertures could be used. For cheaper lenses such as 50mm f1.8 or f1.4, the aperture would be better at 1 - 2. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Bust photography lens and aperture
When shooting a half-length portrait, the aperture could be chosen from F1.2 to F4, the sensitivity was set to 100, the focal length was the widest, and the exposure of the person's face was the standard. The color of the clothes had to be distinguished from the background. The smaller the aperture value, the larger the opening and closing aperture (large aperture), allowing more light to enter the camera sensor. The image outside the focused object would be more blurred and the subject would be highlighted. The larger the aperture value, the smaller the opening and closing aperture (small aperture), the less light entering the camera sensor, and the overall image would look clearer. Different apertures had different effects and uses in a half-body portrait. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Football match lens aperture
When shooting football matches, the aperture of different camera lenses varied. For example, a Pentax camera lens might use a lens such as the Pentax DFA70 - 200/2.8 when shooting a football match, with an aperture of f/2.8; a Nikon camera lens such as the Nikon D810 (stand-alone) had an aperture of f/4.8 when shooting a football match; a Canon camera lens such as the Canon RF600mm F11IS ATM had an aperture of f/11, and a Canon RF800mm F11IS ATM also had an aperture of f/11. In addition, in some other scenes of football games, there were also lenses with apertures of f/2.8, f/4.5, f/6.3, etc. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Dispersion dynamic control reaction model
Diffusion - kinetic - controlled reaction model <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>