Introduction course of SLR camera photography

What are the basic knowledge of SLR photography? What skills do you need to master? Below I have sorted out the basic knowledge and skills necessary for getting started with SLR photography, hoping to help you!

1, aperture

The aperture size is controlled by the aperture blade inside the lens, which refers to the amount of light passing through the lens and directly affects the imaging quality of the picture. Apertures are like faucets. When it is turned on, the current is also large. If you turn it down, the water flow will also decrease. The larger the aperture, the greater the light input, and the smaller the aperture, the smaller the light input. The larger the f value of the aperture, the smaller the aperture; The smaller the f value, the larger the aperture.

Extended knowledge: Why the smaller the aperture value, the larger the aperture? Why is it inversely proportional? Look at the picture below to know the answer:

2. Shutter

Many people think that the shutter of a camera is as fast as pressing the shutter. Wrong, shutter refers to the length of time that light shines on the image sensor through the lens. Let's take a look at the photos taken by different shutters. The first one is 1/500 seconds, and the second one is 4 seconds rendering, so what shutter to use depends entirely on what effect you want:

3, high-definition specifications

Hd specifications are generally divided into 1080P, 1080I and 720P(i stands for interlaced scanning and p stands for progressive scanning). 720P is called standard definition, which is a display format with a resolution of 1280×720 under progressive scanning. 1080I is called quasi-HD, and it is a display format with the resolution of 1920× 1080 under interlaced scanning. 1080P is called full HD, which is a display format with a resolution of 1920× 1080 under progressive scanning.

4, the number of pixels

The number of pixels in a digital camera includes effective pixels and maximum pixels. Effective pixel: refers to the pixel value that really participates in photosensitive imaging. Maximum pixel: refers to the real pixel of photosensitive device. This data usually includes the non-imaging part of the photosensitive device. For example, the maximum pixel of Nikon D800 image sensor is 36.8 million, but actually only 36.3 million pixels participate in photosensitive imaging, so we call it effective pixel.

5. Image sensor

Image sensors can be divided into CCD and CMOS according to different materials. CCD is called charge coupled device, and CMOS is called complementary metal oxide semiconductor. With the development of science and technology, the comprehensive performance of CMOS is better than CCD, so almost all SLR image sensors use CMOS at present. The following are their advantages and disadvantages:

Step 6 expose

Exposure refers to the brightness of photos, which is determined by the relationship between shutter and aperture. The picture below is an example. Filling a glass of water represents accurate exposure, so the bigger your faucet (aperture), the shorter the time to fill a glass of water (shutter); On the contrary, the smaller the faucet (aperture) is, the longer it takes (shutter).

7. Automatic exposure mode

Generally speaking, there are three automatic exposure modes: shutter priority automatic exposure (TV), aperture priority automatic exposure (AV) and program automatic exposure (P). What do these three modes mean? To put it bluntly, it can be understood that shutter priority automatic exposure means that you have the final say, you can control the shutter, but the aperture is determined by the camera. Aperture priority automatic exposure means that the aperture value can be adjusted at will, but the shutter speed is determined by the camera. Automatic exposure means that the shutter speed and aperture value are determined by the camera, and you have no right to adjust them. Generally speaking, when shooting moving things, use the shutter to give priority to automatic exposure; If you shoot something that is dead and can't move, you should use the aperture to give priority to automatic exposure. When you are not sure whether the lens is moving or still, you should use the program to automatically expose it, and the camera will automatically recognize it, such as when taking a snapshot.

8. Manual exposure (M file)

M-range means that the photographer determines the exposure value of the camera by adjusting the shutter and aperture value. It means that the aperture and shutter speed are up to you. Often used for night photography and sports photography. I don't recommend the manual exposure mode for beginners, because you haven't reached a certain level. Unless you think that in this complicated lighting environment, you can control the shutter and aperture value more accurately than the intelligent recognition of the camera, otherwise I suggest that the effect of shooting directly with intelligence will be better:

9, exposure compensation

Exposure compensation is like filling a pool with water. Not without it, not without it. It must have just been filled.

If overexposed, the color information of the photo will be diluted by high brightness, and the level details will be seriously lost, showing sparkle.

If the exposure is insufficient, the scene of the picture will be dim, the picture will be turbid, and the level details will be seriously lost, showing a black color.