1. exposure: What are aperture, shutter speed and ISO, and how to control exposure parameters? (1) Aperture controls the amount of light entering, and the formats are F 1/2.8 and F 1/8. The smaller the number, the greater the amount of light and the brighter the picture. The amount of light entering is inversely proportional to the square of the aperture value. For example, the amount of light entering F4 is four times that of F8. Because in photography, the amount of light entering is doubled with each additional exposure, the standard aperture classification is: F 1.4, F2, F2.8, F4, F5.6, F8, F 1 1 6, with a difference of one for every two. Aperture not only affects the amount of light, but also affects the depth of field. The larger the aperture, the shallower the depth of field, that is, the shallower the clear part of the picture and the more blurred the background. We often see photos with empty background and clear subject on the Internet, all of which are taken with large aperture. Generally speaking, we use a large aperture to shoot portraits and still lives, so as to achieve the effect of highlighting the subject. At the same time, shoot the scenery with a relatively small aperture, such as F8, so that all parts of the photo are clear. (2) The shutter controls the exposure time, and the format is 1/2000s, 1/50s, where 0.5s has the shortest first exposure time and the longest last exposure time. Double the shutter time and double the amount of light. The standard shutter classification is 1/4000s, 6500. 1/500s， 1/250s， 1/ 120s， 1/60s， 1/30s， 1/ 1.5s，6550。 The faster the shutter speed, the shorter the capture moment. Then the less the subject moves in this short period of time, the more difficult it is to record the jitter of the person holding the camera. There is a so-called safety shutter in photography, that is, as long as the shutter speed is higher than this value, the picture will not paste. This value is the reciprocal of the equivalent focal length. For example, if the focal length of the lens on d5 100 is adjusted to 35mm and the equivalent focal length is 52mm, then the value of the safety shutter is 1/50s. If it is higher than this value, such as 1/30s, it is easy to burn out. If the camera or lens has anti-shake function, it can be downgraded by 2-5 levels. For example, the anti-shake of a 55-200VR lens is almost 4 gears, so when the focal length is 200mm, the equivalent focal length is 300mm, and the anti-shake safety shutter is 1/250s does not open. This shutter speed is usually too dark when shooting indoors or at night. However, if the lens is turned on for anti-shake, the shutter speed can be lowered to115s, which can meet the needs of most dark shooting. If you shoot a child, because the child is always moving, the shutter often has to be lowered below11000 s before shooting. (3)ISO is the sensitivity. Under the same aperture and shutter settings, the higher the sensitivity, the brighter the picture. However, the higher the ISO, especially after exceeding a certain range, the imaging quality will often deteriorate, and a lot of white noise will appear on the screen. The ISO of most APS-C format SLR is best set below 800. A better one can be set to 1600, and a worse one, such as 600d, may only be set to 400. ISO classification:100,200,400,800,1600,3200,6400,12800,25600. The increase of aperture is equivalent to the increase of shutter speed and iso speed. (4) How to set exposure parameters in actual shooting? Generally speaking, the aperture is determined according to the required depth of field. Portraits and still lifes generally use the maximum aperture, such as f1.8; For scenery, adjust it to a medium aperture, such as F8; Then adjust the shutter speed to a safe shutter, such as 50mm for 35mm, and the shutter is1/50; Then set the ISO to the lowest level, such as ISO 100. If you want to save trouble, then you can set the mode to P and turn down the ISO.
2, color: clever use of white balance and color temperature settings. (1) All cameras have a white balance setting, and some even have a color temperature K setting. The lower the color temperature value is set, the higher the actual color temperature after white balance compensation, and the bluer and colder it feels. On the contrary, it is yellow and warm. Generally, shooting snow scenes and snow-capped mountains is usually set at a low K value (such as 2500k). When shooting a sunset, autumn scenery usually uses a high K setting (such as 7000k). (2) If the entry camera does not have the function of setting the color temperature K value, you can use cloudy shadows instead of high K value setting, and use incandescent lamp mode to lower K value setting.
3. Some shooting skills. (1) Find a picture with people and scenery, and try to shoot it with different focal lengths and different apertures, so as to realize the change of perspective relationship caused by focal length change (for example, if you shoot a full-length portrait, the perspective relationship will also change if you use 200mm more backward than 50mm) and the change of depth of field caused by aperture change. (2) In addition to the standard lens with large aperture (such as 50/ 1.8 lens), try to shoot portraits with telephoto end, so that people and background will be compressed together and there will be a sense of separation. (3) The same is true for shooting scenery. Try the telephoto end more. If the focal length is not enough, only a small part of the picture can be cropped after shooting, which is the same as shooting with a telephoto lens. At present, the camera pixel is very high, but the resolution of uploading to the internet is generally several hundred, so don't be afraid of cropping. (4) Light is very important. The sunshine is the most beautiful about two hours before dark. At this time, you can find a beautiful place to take pictures outside and try the effects of lighting, backlighting and metering. At this time, it is also appropriate to go to the coffee shop and find a window facing west to sit down, and use the gentle sunshine and the decorative ornaments in the coffee shop to shoot some beautiful sugar water, busts and still lives with a large aperture lens.