I like SLR and started a Canon 100d, but I don't know much about the basics. Ask God for advice and tell me the depth of field exposure.

These Baidu have, let me help you integrate and summarize.

Depth of field: the depth of field refers to the range of the distance between the front and back of the subject measured by imaging in front of the camera lens or other imagers. After focusing, a clear image can be formed in the range before and after focusing, which is called the depth of field. There is a certain length of space in front of the lens (before and after focal length adjustment). When the subject is located in this space, its imaging on the negative is just between the two diffusion circles before and after focusing. The length of the space where the subject is located is called the depth of field. In other words, the blur of the image presented by the subject on the negative plane of this space is within the limited range of the allowable circle of dispersion, and the length of this space is the depth of field.

Exposure: exposure, that is, the mode that the computer uses natural light source, is usually divided into manual exposure, AE lock and other modes. The quality of the photo is related to the exposure, that is to say, how much light is needed to make the CCD get a clear image. Exposure is determined by the light passing time (shutter speed) and the light passing mask (aperture size).

Aperture: the difference of depth of field. The larger the aperture, such as 1.4, 1.8, 2.0, usually the background is blurred, and only the subject is clear. The ones with small aperture, such as F8+06, have good scenery and clear distant places, but the shutter requirements are different. The large aperture is higher than the shutter speed.

Numbers on the lens: Take Canon lens as an example, I use EF? 24- 105mm？ 1:4 L is USM.

Among them, EF is the interface mode, Canon is divided into EF port and EF-S, EF lens can be used for fully equipped cameras and non-fully equipped cameras, and EF-S interface lens can only be used for non-fully equipped cameras.

24- 105mm refers to the zoom lens, and the zoom range is from 24mm wide-angle end to 105mm telephoto end.

1:4 means the aperture size is, I mean the aperture is constant at 4? Some lenses write 3.6-5.2 or something else, but the maximum aperture at the wide-angle end is 3.6 and the maximum aperture at the telephoto end is 5.2.

It is the Canon lens that represents the anti-shake function of the lens. Camera bodies are divided into those with and without anti-shake, and lenses also have anti-shake function and those without anti-shake. The IS sign indicates that the lens has anti-shake function.

USM means that the lens is equipped with an ultrasonic motor, and the lens equipped with USM is fast and quiet when autofocusing.

Other manufacturers have different lens recognition rules, but the recognition of focal length and aperture is generally easy to identify. In addition, such as anti-shake, focus motor, special lens, etc., each logo is different.

It is suggested that the landlord explain which manufacturer's lens is when asking questions.

? In addition, there will be some numbers next to the lens, indicating the caliber of the lens. For example, my lens is

? Φ 77mm means that my lens aperture is 77mm, and I have to buy a 77 mm UV mirror when cultivating.

Source: Baidu knows.