Basic knowledge of SLR

Photography is a tool for people to record the objective world. 1837 as a science and technology, since its birth, its development and progress in all stages are inseparable from the perfect combination of humanities and technology, showing increasingly obvious characteristics of the times, profoundly affecting people's daily lives and playing a positive role in the development of world culture and art. The following is the basic knowledge of SLR compiled by me for your reference!

SLR 1 Basic knowledge: photography? Ideas?

SLR cameras imitate people's vision, and what you see with your eyes can be accurately restored into photos with SLR cameras and passed on to others, so that they can be there.

When we pick up the camera to take pictures, the question is in front of us: What do you want to take? Or what do you want to convey through photos, a person, a thing, or a person? The expression of photography is like writing an article. Before writing, you should write for your article? Ideas? Create the central idea of an article. Also known as the entertainment center.

Create a photo? Ideas? This is very important. Don't wait for the same photo? Scrap film? . Looking at a photo is like listening to a song? Incoherent? You can't understand what he is trying to say.

A photo can only be used to explain one thing!

If we try to express many problems in one photo, it can be said that it is a failure. It is also beautiful and interesting to be reluctant to part with many useless elements when composing music. Many beautiful things together cause the observer's visual roaming, thus making? Ideas? Falling.

Painting composition is addition, and simple photographic composition is subtraction. The real photographic composition is to increase information and elements as much as possible without affecting the concept of the picture. Everything depends on the purpose of communication (except for special photography such as photo id or portrait).

Basic knowledge of SLR II: Basic knowledge

1. Holding the camera in a correct posture can effectively avoid camera shake. Avoid holding it with one hand. When holding with both hands, one hand holds the camera handle and the other hand holds the zoom or focus ring of the lens. Don't put your hands in a straight line, but form an included angle, which is relatively more stable. When holding the camera, the big arm should clamp the body hard. Relax your small arms, or they will shake easily. The two arms are staggered one after the other to form a stable included angle. ：

2. Use optical viewfinder or EVF viewfinder. Triangular support is the most stable. Use the optical or EVF viewfinder to find the scenery. Try to avoid using LCD to find views. Because of the optical or EVF viewfinder, people's brow bones can be tightly attached to the viewfinder. With the cooperation of hands, a triangular stable support can be formed.

3. Correct standing posture. When shooting, you should step forward. Don't put your feet in a straight line after one foot. In addition, when shooting, the thighs should be tightened and the calves should be relaxed to avoid the foundation shaking affecting stability.

4. Learn to adjust your heartbeat and breathing. Because of heartbeat and breathing, people are actually shaking at any time. But we can take a deep breath to stabilize ourselves, and then exhale and inhale smoothly. Hold your breath when you press the shutter to minimize jitter.

5, learn to press the shutter half. Don't just press the shutter when you see the scene. The stroke of the camera shutter is divided into two steps, that is, the camera starts autofocus and photometry by pressing the shutter half-way, and then it will start by pressing the shutter fully. Otherwise, you can't measure or focus correctly, the image is virtual and the exposure is not accurate. When you press the shutter, it should be smooth and soft.

6. Exposure within the safe shutter time range. (See shutter introduction for details)

7. Try to turn on anti-shake when holding it. When installing the tripod, please turn off the anti-shake to avoid the interference of the anti-shake system.

8. Don't take pictures with your camera bag on your back or something in your hand. If you are exposed for a long time, put down all your equipment, and the extra load will make your body out of balance. It is easy to cause physical fatigue and jitter.

9. Find a stable support. If the shutter speed displayed by the metering value is much longer than the safe shutter speed, and there is no tripod at hand, you can find some stable brackets for emergency shooting. For example, leaning against a tree or a wall is more stable than standing without support. The exposure time is 1? In the case of 3 seconds, you can often get good results by pressing the camera tightly on the bracket with both hands to keep it stable. Sometimes, you can put the camera directly on the ground or on the wall to shoot. Its stability is comparable to a tripod. If you are shooting scenery and other objects, you can also put the camera in the camera bag or bean bag to take a selfie. Bean bag is a kind of bag filled with beans or ceramsite, which can be deformed at will and is not easy to wear the camera.

10, make good use of tripods and monopods. ? How does a tripod look at photographers? . The biggest trouble for people who have just started to touch the camera is that the hand holding the camera can't keep steady and shake. Although many cameras have anti-shake function, they can't cope with large jitter. Especially when shooting at night, jitter is more likely to cause inaccurate focus and blurred photos. Besides shooting more and practicing more, shooting with a camera on a tripod is the most reliable.

1 1, make good use of RAW format! If the memory card is large enough for the landscape, use the RAW format. In this way, more light and dark details can be preserved, and it is easier to correct the white balance and tone, which provides the maximum space for post-processing.

Basic knowledge of SLR 3: aperture

In the lens, there is a circular aperture with variable aperture. This structure is called an aperture. The blades that make up the aperture are called. Aperture blade? . (Theoretically, the more blades, the more natural and round Jiao Wai). The aperture on the fuselage is generally f? For example, F8 f 5.6, F 16. We call it aperture value, or aperture for short. The larger the number, the smaller the aperture.

Figuratively speaking, the aperture is the pupil.

The light is dark, the pupils are dilated, and the amount of light entering increases. The light is strong, the pupil is narrowed, and the amount of light entering is reduced.

The aperture size determines the amount of light passing through per unit time. The greater the value of f, the more light passes through it.

The function of aperture is similar to the picture below? Valve? The tap switch is light)

Iso is fixed, the smaller the aperture, the slower the shutter, and the larger the aperture, the faster the shutter.

Conclusion:

Large aperture, shallow depth of field, blurred background. Under the same conditions, increase the shutter speed (shoot more people) (for example, F 1.8).

Small aperture, deep scenery and clear front and back. Under the same conditions, lower the shutter speed (use more large scenes) (such as F22).

Theoretically, the larger the aperture is, the better the imaging quality will be, but with the increase of aperture, the aberration will increase sharply, resulting in poor imaging quality. In addition, a small aperture will produce diffraction (in digital photography, a small aperture will increase the exposure time and make the image appear noise), which will reduce the image quality. Therefore, the best aperture value is the balance point to avoid the above two phenomena, that is, the maximum aperture value is low 1 to level 2. For example, 50 F 1.8, reduce it to F4 for best definition!

Optimum aperture:

The best aperture means that any lens, whether fixed focus or zoom lens, has the best aperture or aperture. At this or these apertures, the resolution of the lens can reach the maximum, that is, the maximum resolution can be achieved. The maximum resolution does not refer to the clear range (that is, it is not the depth of field).

The best aperture of an ordinary lens is often in the range of f5.6-f 1 1, so why? No dog head under f8? Statement. And the advanced lens, which is what? Tauren? Its optimal aperture is often relatively large, and even when it is fully open, it may be relatively sharp. This is also one of the reasons why people pay high prices to buy cow heads. They entered the bull's head, not only for the sake of out-of-focus imaging, but also for the pursuit of high resolution under large aperture.

The best aperture of the standard lens of F 1.2-F 1.4 is F4;

The best aperture of the standard lens of F 1.8-F2 is F4-f 5.6；;

The best aperture of F2-F2.8 fixed-focus lens is F4-f 5.6；;

The best aperture of F2.8 constant zoom lens is F5.6

The best aperture of F3.5-F5.6 zoom lens is F8;

The best aperture of F4.5-F5.6 zoom lens is F8-F 1 1.

(Data are for reference only)

note:

A-file aperture is preferred (photographers often use this file)

1. Whatever you shoot, don't shoot with the maximum aperture unless you want to keep the safety shutter.

2. Please try to use the aperture of F8~F 1 1 when shooting scenery.

3. When shooting close-ups of people and still life, the maximum aperture can be reduced by 1~2.

Please try to control the safety shutter above the reciprocal of the focal length. The wide-angle shutter should also be above 1/30 seconds. If the shutter is insufficient, please increase the aperture or ISO.

Basic knowledge of SLR 4: shutter

Shutter is a device for controlling exposure time in camera.

In fact, shutter is short for shutter speed. The so-called shutter speed means that when the shutter is pressed, the mirror turns up, the shutter blade opens to make the photosensitive element photosensitive, and when the shutter blade closes, the photosensitive element stops photosensitive. This time interval is called shutter speed, or shutter for short. In those years when photography was just invented, it usually took several minutes to take a photo. Most cameras don't need a shutter. At the beginning of exposure, take off the lens cover, then look at the watch. After five minutes, cover it and the photo will be finished.

Later, the photographic speed of film became faster and faster (ISO became higher and higher), and the exposure time became one minute, several seconds,110 second or even one hundredth of a second. It's not fast enough to hold the lens cover by hand at this time. We need something that can accurately control the exposure time, and this thing is the shutter. Shutters include mechanical shutter, electronic shutter and electromechanical combination shutter.

Safety shutter: The safety shutter is about the reciprocal of the focal length.

For example, when using a 35mm lens, the shutter speed should not be lower than 1/35s, and when using a 200mm lens, the shutter speed should not be lower than 1/200s, otherwise the picture may be pasted. (Some lenses have anti-shake function, which can still reduce the shutter speed 1-2 under the safety shutter. )

Shutter and aperture match.

If you take a snapshot, you need shutter priority. (Improve iso, short focal length, large aperture, tripod, and all other tools that can accelerate)

Pay attention to the safety shutter when shooting the stage.

1/4000 shutter can capture the moment.

The flow at night is 10s+, and the shutter of the flow is slightly longer, 0.5s and1s..

B-door function, from pressing to releasing, shutter opening and closing time is controlled by yourself. ：

Basic knowledge of SLR 5: ISO sensitivity

ISO sensitivity: refers to the photosensitive capacity of photosensitive elements. In the film era, the sensitivity is constant, and a film has only one sensitivity. Because the film is produced by the factory, the amount of silver salt on the film has been decided and cannot be changed. In the digital age, CCD/CMOS is a photosensitive element, and the current generated after receiving light can be adjusted by an amplifier, so the sensitivity is variable. The abbreviation of sensitivity is ISO. The higher the sensitivity, the stronger the sensitivity of the photosensitive element. Under the same aperture shutter condition, the higher the sensitivity, the brighter the picture.

Under the same conditions, the lower the ISO, the better the picture quality! The higher the ISO, the faster the shutter!

Although the high ISO is fast, the enlarged image is rough (that is, the noise is large), so it is impossible to draw a fine picture. Therefore, landscape photography should use the lowest sensitivity! Use high ISO only as a last resort!

For D3 100: It is recommended that 100,200 be sunny. Cloudy day 200? 800, hand-held at night, snapshot 1600, tripod available 100.

Basic knowledge of SLR 6: metering and exposure

Photometry is a machine to judge the intensity and brightness of light.

Measurement method: generally, it is matrix, central and point measurement.

1. Don't point to the sky, don't point to the darkest place. Grab the middle value.

2. Because the machine is convenient in the later stage, the automatic exposure will be underexposed, resulting in gray, white and black. Therefore, it is necessary to increase the exposure when encountering white, and reduce the exposure when encountering black!

3. Make good use of measurement methods (weighing measurement, point measurement, center key measurement ...) according to the subject matter you shoot.

4. If you are not sure about metering, please lock the gray things around with AE lock before shooting.

5。 For M file, photometry is invalid, but it will affect the information prompt of LCD histogram.

Manual metering:

1. Find the block in the picture that is close to 18% gray level.

When the shooting experience is gradually accumulated, it is easy for us to find the place where the reflectivity is close to 18% in a picture. It may be the sky, the asphalt pavement in the sun, the green grass, or the unpainted wall. Experience can help us to confirm on-site metering. You should do more, then observe the results and correct your judgment.

2. Use a gray card or palm to measure light.

If you don't have experience to judge the middle tone or the environment is chaotic, you can directly put the gray card under the ambient light source to directly measure the light. If there is no gray card, you can use your own palm instead. People's skin color is close to the gray tone of 18%, so the hand is actually a very useful gray card. But remember not to use the suntanned back of your hand. This will affect the photometric results.

Exposure accuracy: