Summary of basic theory of photography?

Basic theoretical knowledge of photography

The basic theoretical knowledge of photography, for beginners who have just come into contact with photography, will be very curious about all kinds of knowledge of photography, which can improve our photography ability. Let me share with you the basic theoretical knowledge of photography.

Basic theoretical knowledge of photography 1

1, exposure: the brightness of the picture, where overexposure means that the picture is too bright, underexposure means that the picture is dark, and correct exposure means that the brightness is normal.

2. Aperture: The aperture of light entering the camera is controlled on the lens, which is a coefficient. The larger the aperture, the more light enters and the brighter the picture; Conversely, the smaller the aperture, the darker the picture.

3. Shutter speed: it is the length of light entering. The longer the time, the more light, and the brighter the picture. Conversely, the shorter the time, the darker the picture. High-speed shutter means fast shutter speed and short exposure time; Slow shutter speed means slow shutter speed and long exposure time.

4. Sensitivity: It is the ability to feel light. The higher the sensitivity, the more sensitive to light and the higher the picture; Conversely, the smaller the sensitivity, the darker the picture.

5. Reciprocity law (reciprocity rate): Under the condition of constant exposure, various combinations of aperture, shutter and sensitivity, such as increasing aperture, increasing light input, and reducing shutter speed and sensitivity according to the corresponding light input, achieve a balanced relationship.

6. Depth of field: it is the size of the clear range in our picture. The depth of the scene indicates that the clear range is small, and then the background will be blurred; A large depth of field means a wide range of definition, indicating that the foreground background is very clear.

7. Focus: the operation that enables us to take a clear image of the subject. There are many kinds of focusing methods. Manual focusing is manual control, autofocus is camera-controlled focusing operation, single autofocus is focusing once, intelligent servo autofocus is keeping focusing operation as the object moves, and full autofocus is camera-completed focusing operation.

8. Photometry: measure the light of the picture and provide correct exposure parameters: shutter aperture sensitivity, etc. There are several metering modes, evaluation metering is to average all areas of the picture, center key metering is to meter the area in the center of the picture 1/3, and spot metering is to meter a single point and a small area.

9. White balance: Make the picture appear closer to the real color tone. The picture is here in Huangshi. If you lower the k value, the picture will be close to the normal color. When the picture is blue, increase the value of k, and the picture will be close to the normal color; When we want warm yellow tones, we can increase the K value, and when we want cool blue tones, we can decrease the K value.

10, exposure compensation: after we set the exposure, we will increase the exposure compensation of the whole picture to increase the brightness; Reduce exposure compensation and reduce brightness.

1 1, JPEG and RAW: the storage format of camera images, JPEG can be viewed and transmitted directly on the computer, and RAW format can completely record the later parameters, but it cannot be viewed directly on the computer.

12, wide-angle and telephoto: the wide-angle lens has a short focal length and a larger viewing angle, which can accommodate more content into the picture; A telephoto lens has a long focal length and a small viewing angle, but it can narrow the visual distance from the subject, just like zooming in. For example, our thumb presses our index finger into a circle, and the wide angle is what we see when we put the circle close to our glasses and see more; The telephoto is that the circle is far away from us, and the picture seen through the circle becomes less.

13, exposure mode: the automatic shift is controlled by the camera itself, and the program can automatically adjust the exposure compensation to complete shooting. The aperture priority is to control the aperture and shutter speed sensitivity automatically, the shutter priority is to control the shutter speed and aperture sensitivity automatically, and the manual M shift is to manually control all parameters.

14, multiple exposure: creative pictures with multiple pictures superimposed by the camera's internal algorithm.

15, HDR: The dynamic range is high, and the correct exposure function can be synthesized by multiple pictures with different exposures.

16, composition: the distribution of the main body of the picture, different distribution has different artistic beauty.

17. Press the shutter: When pressing the shutter, we have two operations, half-pressing the shutter and full-pressing the shutter. Half-pressing the shutter will focus on metering normally, and after fully pressing the shutter, release the shutter to complete shooting.

18. Photographic filter: polarizer eliminates reflection, subtracter reduces light, medium gray gradient lens ensures correct exposure of bright and dark parts when shooting large light ratio, and ultraviolet rays are filtered by uv filter.

19, tripod: equipment for stabilizing the camera, often used for slow door and long-distance shooting.

20. Pull wire release: Set the timing continuous shooting through pull wire release to reduce jitter.

Basic theoretical knowledge of photography II

First, exposure

Exposure in photography simply refers to the process that light enters the camera and leaves an image on the photosensitive element inside the camera. The size of the aperture and the speed of the shutter determine the exposure, while ISO determines the exposure speed of the camera. According to the intensity of light entering the camera, photographic exposure is usually divided into normal exposure, underexposure and overexposure.

Second, measurement.

In order to get accurate exposure, it is necessary to measure light when shooting. Photometry in photography is realized by the camera's built-in photometry system and external exposure meter. Because the external exposure meter is rarely used, the metering mentioned now is mainly aimed at the built-in metering system of the camera.

Simply put, the camera measures the light of the scene through the photometric system, and gets a correct exposure value, and then sets the appropriate aperture and shutter according to this exposure value. This process of measuring exposure value is called photometry. Taking Canon as an example, the built-in metering system of the camera can be divided into evaluation metering, partial metering, spot metering and central metering.

Third, focus.

Focusing is one of the important links in shooting. When shooting, if the focus is not accurate, the picture will be blurred, even after the later period, it is irreparable. Camera focusing can be divided into automatic focusing and manual focusing. Usually, when we shoot with the shutter half pressed, we often hear a beep, which is a hint of successful focusing through the camera's autofocus function. Auto-focus is divided into single auto-focus, continuous auto-focus and intelligent auto-focus according to the number of focusing times during shooting.

Four, aperture, shutter, ISO

The aperture shutter ISO can be said to be the most important thing in photography. All the shooting is realized around these three changes. Because the knowledge of the three is relatively large, I won't talk about them one by one here, but only explain their respective functions, so that beginners can have a general understanding and lay the foundation for subsequent learning. The so-called aperture is a large or small round hole composed of a group of small iron sheets on the lens.

Basic theoretical knowledge of photography III

The three basic knowledge of photography are the flexible use of focal length, the use of light and the focusing of eyes.

1, eyes are the key.

The most important thing in portrait photos is the characteristics and charm of the characters. If the characteristics and charm of the characters can't be displayed, then the portrait notes will look dim. And people's eyes are the windows to the soul. If you want to show the charm of the characters, you must catch people's eyes. This is also the reason why many photographers emphasize the focus on the eyes of the characters when taking portraits.

2. Use of light

Portrait shooting can capture the characteristics of people under different light and scenery. If you want to use different lights to capture the characteristics of people, then you must understand and use light.

3. Actively use the coke part

Different focal lengths and different lenses have different shooting effects, depending on how you choose. Generally speaking, 35mm is more suitable for taking full-length portraits, and at the same time, the surrounding pictures can be taken in. However, the wider the focal length of the lens, the higher the requirements for the background, and the background should be concise and clear, which will not interfere with the characters.

Precautions:

1. The closer to the subject, the larger the irradiation area and the softer the light quality.

2. When filling the light, be sure to lift the reflector above your head to fill the light. This light supplement effect comes from the upper part of the main body, which is harmonious and natural. If you put it on your chest to fill the light, the light source will come from below the subject, which will cause ugly bottom light effect, which is a mistake that many photographers are prone to make.

3. When using the reflector to fill the light, shake the reflector left and right, and carefully observe whether the position of the fill light is accurate and effective.