Please tell me, how does Nikon D300 measure light accurately?

I'll give you another one. It is well written.

How to use the metering mode of digital camera correctly-Pan Lei, a senior cinematographer in Yangquan.

Metering mode: There are basically three metering modes for digital cameras:

1. average photometry: calculate the average photometry value of the whole scenic spot. This is the default basic metering mode of general cameras, and the usage rate is the most common. You can almost take a satisfactory photo when the light is even and the contrast between light and dark is not great within the framing range. For example, the light of the scene at that time was very flat, and the color and light of the main body in the scenic spot were relatively general. Using the average metering mode, you can get photos with correct exposure.

2. Central average metering: It is a metering mode based on the area average metering of about 30% in the middle of the framing range. When the subject to be represented is in the middle of the framing range, and there is a big difference between the light and dark environment and the subject, choosing the center average metering and focusing on most areas in the center can make the exposure of the subject more accurate. For example, the idea of a movie is to highlight a sense of oppression with the prospect and show respect for the subject. When shooting, the proportion of light between the subject and the foreground is quite different. Using the central average metering mode, the overall metering is mainly in the middle of the view, and the photos with appropriate exposure and foreground silhouette are taken. To achieve the design goal, if the average metering mode is used, the subject may be slightly overexposed, leaving too many details in the foreground shadow, making the picture appear messy.

3. Spot metering: also known as key metering, it is the area metering within the framing range. In actual shooting, the spot metering mode is rarely used and it is not easy to master. But in some cases, spot metering can play an important role. Knowing when spot metering should be used and using spot metering correctly can make the exposure of the subject accurate on the one hand, and create wonderful pictures that can't be seen in reality by using "sensitivity tolerance" on the other hand.

The application of spot metering mode is: the spot metering mode is suitable when the light distribution is uneven and the contrast is large within the range of framing. In this case, if spot metering is not used, the exposure of the object to be represented may be incorrect, too bright or too dark for white to have details.

Use exposure lock: Before using spot metering mode, you need to know how to use exposure lock. The metering point of the camera fixed-point metering is in the center of the scenic spot. When using spot metering, it is necessary to aim the center point of the scenic spot (the metering point of spot metering) at the subject to be represented to measure the light. If the subject is not in the viewing center you want to display, you can first aim the metering point of spot metering at the subject and use the camera's

The exposure lock function locks the data of the subject's photometry, and finally re-composes according to your own ideas, and then presses the shutter after focusing.

Most cameras have a special exposure lock button, which is convenient for us to reconsider the composition after exposure lock. However, there are also some cameras whose exposure locking and focusing are achieved by half-pressing the shutter, if the metering point and the focus point are inconsistent. For example, when shooting the sunrise, the light measuring point in the frame is on the cloud near the sun, so we need to focus on the building. At this time, we need to show the photometric points of buildings or people first, then click the exposure lock button, and then re-compose the main performance object for shooting.

Some cameras cannot provide separate exposure lock and focus lock. You can also record the exposure data after turning on the subject, then set the camera shooting mode to M file, set the exposure data according to the turned-on data, and then focus on the composition. For example, from the perspective of framing environment, the main object to be represented is bright, while the accompanying object is dark, and the light around the main body is uneven, which affects the composition. If the light is measured by the average value, the average light measurement value will be biased towards the light intensity in the dark environment, and the result obtained by shooting is that the bright part is exposed correctly, while the main objects we want to show are overexposed, and some are dull and without layers.

Sometimes, the lack of exposure lock is also the charm of photography. Although what it reflects is true, it is different from what it really sees because of the sensitivity of film (or ccd, etc.). ) It's too narrow. It can be said that if you don't use a camera to shoot, you can't see such an effect with the naked eye. By understanding the sensitivity, we can predict the shooting effect, and use spot metering to extract an interesting film from the messy and ordinary scenery.

People should also pay attention to metering. The most important thing in portrait photography is usually to show people's faces. Using natural light, the face is measured when shooting, so that the face is exposed correctly, and the surrounding environment and clothes are darkened due to insufficient exposure. The picture is simple and the characters are prominent, which is similar to the feeling of background cloth used in the studio. If you use general photometry, the surrounding environment will be clearer, and if you are overexposed, your face will be pale or dim. In fact, when shooting, the environment seen by naked eyes is very bright, and the ground reflecting sunlight is exposure value, which darkens the surrounding environment and highlights some reflected light and people, thus creating this feeling. If you use average metering, you will get a film with normal exposure and bright surrounding environment. When shooting, measure the bright part of the reflection first, and then focus on the subject after locking the exposure. Spot measurement plays an important role in shooting the whole picture, making the exposure of bright places correct, forming a contrast between light and dark, and highlighting the characteristics of the subject.

Beginner photographers should: 1 understand the application of average metering mode, central key metering mode and spot metering mode. 2. Understand the usage of exposure locking; 3. Using the "spot metering" method, you can get accurate object exposure. Through understanding and mastering the basic knowledge, through practical attempts and accumulated experience, film friends can also take satisfactory and surprising photos.