Traditional Culture Encyclopedia - Photography and portraiture - How do novice photographers accurately master photographic exposure?

How do novice photographers accurately master photographic exposure?

Lead: It doesn't matter! In fact, photography has some rules to follow. As long as you understand the principle, you will have a well-thought-out plan in setting parameters. The following rules are actually not difficult to understand. Let's join our course.

Determination standard of exposure parameters

For the same scene, according to the equivalence of exposure, there will be many different exposure combinations that can get the same exposure, so the final effect of each combination is exactly the same? The answer is definitely different, because shutter speed, aperture value and ISO value can not only control exposure, but also produce different picture effects. So how should we make a decision when shooting?

ISO value: ISO value affects the picture effect mainly because the picture taken with high ISO value will be rough, because noise and particles will increase. So in general, the ISO value needs to be set as small as possible. For example, it can be set to ISO 100 when it is outdoors on sunny days. In indoor lighting, due to the weak light, it is necessary to improve the ISO value to about ISO 400 ~ ISO 800 when shooting with a hand-held camera.

The focal length is 50mm, ISO 50, aperture 1.4 and shutter 1/400.

Shutter speed: There are two conditions to pay attention to in shutter speed. One is to shoot moving objects, such as pedestrians, cars, water and so on. Fast shutter can help to freeze the moment of a moving picture, and slow shutter can shoot motion; Second, the lighting is not very good, and when you shoot with your hands. Try not to let the shutter speed be slower than the safety shutter, otherwise the picture will shake easily.

Aperture: consider the aperture when taking any photo, because the aperture not only affects the brightness of the picture, but also affects the depth of field effect of the picture.

When shooting scenery, the aperture should be smaller, usually set to around f8. If the picture to be shot covers a wide range, such as from the rocks under your feet to the distant sky, the aperture value needs to be set below f 16; The opposite is true when shooting portraits or sketches. In order to highlight people and other subjects and not make the picture look messy, the aperture needs to be larger, generally set to be larger than f4, such as f2.8, or the maximum aperture of some fixed-focus lenses can reach f 1.4, f 1.2 and so on.

Previous textbooks generally recommend using an aperture that is two notches smaller than the maximum aperture of the lens, because the imaging effect of the maximum aperture and the minimum aperture of the lens is often not very sharp. The rapid development of technology makes the imaging quality of lens vary widely. Especially those good lenses, even the maximum aperture or the minimum aperture, still have excellent performance.

For beginners of outdoor shooting, the simpler and more direct criteria for determining exposure parameters can be summarized as follows:

Schematic diagram of f/8 aperture of general shooting range scene

Aperture diagram of large scene f/ 16

ISO value: ISO 100.

Aperture value: the maximum aperture used to shoot people or sketches.

Aperture f/ 16 is used to shoot the scenery extending from the foot to the sky.

Aperture f/8, used to shoot scenes with a small extension.

Shutter speed: given directly by the camera in aperture priority mode, without consideration.

Photometric exposure is free: Sunshine 16 rule?

? Sunshine 16 rule? Is a great rule. What it tells us is that from 2-3 hours after sunrise to 2-3 hours before sunset, the appropriate exposure value of an object in bright sunlight (that is, without the obstruction of clouds, fog and pollution) is: the aperture is equal to f 16, the shutter speed is equal to the reciprocal of ISO value, and all equivalent exposure combinations. In the past, this rule was printed on each film box of Fuji or Kodak negatives. Follow? Sunshine 16 rule? As mentioned above, the environment for applying this law should follow the following points:

The focal length is 24mm, ISO 50, aperture f/ 16 and shutter 2s.

1. Timeliness: 2-3 hours after sunrise and 2-3 hours before sunset. Simply put, it is such a period of time when the sun is high. It can't be that the sun has just come out or is about to set.

2. directivity: it must be the object of sunlight.

3. directness: there can be no clouds or fog, and there can be no or little pollution. The point here is that there can be clouds in the sky, as long as there are no clouds where the sun is.

4. Distance: The subject should not be too close, and the sunshine rule of 16 is not applicable to macro shooting.

5. Uniformity: The subject should be a complex color environment or a single object close to the average tone. If the subject is too white or too dark, you can adjust it slightly.

Let's take a look at the following photo:

Schematic diagram of sunshine rule 16: aperture f/ 16, shutter1100, M7han ISO 100.

From the picture, we can see that the shooting environment is a sunny afternoon, with direct sunlight and full of light. So you can set the aperture to f 16, the ISO value to 100, and then adjust the shutter speed to1100 seconds.

What if it's not sunny and there are no clouds in Wan Li? Isn't there a similar rule? The answer is very affirmative, yes! If the shutter speed is set to the reciprocal of ISO, the F value of moderate exposure is: thin cloud f 1 1 cloudy f8 thick cloud (cloudy day) f5.6 dark cloud f4.

Of course, all exposure combinations equivalent to the above are also possible. Many friends here will ask, what is a thin cloud? What is a dark cloud? It's no use if you don't know how to look at the weather. This kind of worry is meaningful. Let me tell you how to tell.

Focal length 16mm, ISO 100, aperture f/22, shutter 4s.

Sunny days have two characteristics: 1. There will be a little dazzling feeling outdoors; 2. Tall rod-shaped objects (such as telephone poles and people) will leave a deep shadow on the ground. Because if a car is parked on the ground, no matter what the weather is like, there must be a deep shadow under it. Therefore, taller rod-shaped objects have more reference value.

The characteristic of thin clouds is that tall rod-shaped objects still leave shadows on the ground, but the shadows are very shallow.

Cloudy features are: 1. Tall rod-shaped objects have no shadow on the ground; 2. Looking up at the sky, the color of the clouds at the location of the sun is white or light gray, and the clouds at other locations are mostly light gray.

The characteristics of thick clouds are: the color of clouds in the position where the sun is located is light gray or medium gray, and most clouds in other positions are medium gray, and a few may be dark gray.

The characteristics of dark clouds are: the color of clouds in the position where the sun is located is medium gray or dark gray, and most of the clouds in other positions are dark gray, and a small amount may be black.

Night exposure rule

In order to shoot the effect of city lights at night, the appropriate shooting parameters are ISO 100, aperture f 16 and shutter for 30 seconds.

Night Scene 16 Law Works 1 Author M7han

Night Scene 16 Legal Works 2 Author PP008

И o1000 is the best picture quality for the guarantee; Aperture f 16 is to ensure that the picture has enough depth of field, and the second is that a small aperture can turn the city lights into stars; Turning it off for 30 seconds can lengthen the traffic lights in the city into lines, or make the reflection of the lights in the lake very soft. At the same time, the combination of these three parameters can make the brightness of the picture very suitable. The picture below shows the student's application? Night view 16 rule? Are all the photos taken at night nice?

Night Scene 16 Rule Op.3 Tang Dynasty

Night Scene 16 Rule Op.4 Author M7han

If you want to shoot the bright lights of the city and the dreamy colors of the sky at the same time, it is extremely important to grasp the time. Generally, the best shooting time is about 20-30 minutes after sunset. At this time, the light in the sky is already very dark, which can just match the brightness of the city in the light of long-term exposure. If the sky is clear and cloudless, the best shooting time is only 5- 10 minutes; But when there are clouds in the sky, especially low-altitude clouds, with the help of city light, the best shooting time can be extended to 15-20 minutes. At this time, the feeling of clouds moving in the sky will also be recorded by the camera, and the effect is very wonderful and unique.