Analysis of Novice Photography Skills (3)

After troubleshooting the camera, hand shake and other reasons, it is necessary to check whether the lens is dusty or stained. Don't blow with your mouth or wipe with a towel in this situation. Blow the balloon to blow off the dust on the lens, then brush off the debris with a lens brush, and finally wipe it with lens paper to make the lens as bright as new. If there are still sweat stains, fingerprints and oil stains, they should be sent to the camera repair shop to be carefully removed with lens cleaning solution.

3. The main characters are vague and the background is clear.

There are two possibilities. First, when the manual focusing camera focuses, the focus is not on the subject or after the subject is focused, it moves in the composition and does not refocus, so that the subject is not within the depth of field; Second, when using an autofocus camera, the focus is not "locked" by pressing the shutter and then re-composing, so that the focus drifts to other parts of the composition.

4. The first few rows of photos are clear, and the last few rows are blurred.

For multi-row group photos, to ensure that everyone's image is clear, three points must be achieved: First, selective focusing. Five rows of people take a group photo and choose the focus of the second row; Seven rows of people take a group photo, and choose the third row to focus. Second, the aperture should not be set too large, and f4-8 is generally suitable to ensure sufficient depth of field. Third, the shutter speed should not be lower than 1/60 seconds, lest someone turn his head and blur the image.

5. This film has not been exposed.

There are two main reasons: first, the lens cover is forgotten when the paraxial camera shoots, and the scene in the viewfinder is clear, but the imaging light does not enter the lens, and the film is not sensitive. Second, 135 manual film winding of SLR camera is not in place, and the film axis of the cassette is not paid attention to during film winding. Due to the slide of the film head, when the film winding handle is moved, although the shutter has been wound, the counter counts as usual, but the film does not move in the cassette. Although the counter shows that 36 shots have been taken, none of them are actually photosensitive.

6. There are shadows in all four corners of the photo.

There are two main reasons: first, the focal length of the hood and the lens does not match. A wide-angle lens with a focal length of 28mm uses a 50mm standard hood, which will block light from entering the lens. Because the field of vision of the pan-tilt is 47 degrees, and the field of vision of the 28mm wide-angle lens is 75 degrees. Second, when shooting with a 28mm wide-angle lens, a UV lens has been worn on the lens. If you wear a polarizer again, because the polarizer is composed of two pieces of glass with a thick frame, adding it to the frame of the UV lens will inevitably block the light from entering the lens and make the four corners of the photo black. If you need a polarizer when shooting with a wide-angle lens, you must first remove the UV lens and then install the polarizer, so that the picture can receive light evenly.

7. The color tone is dead white or dull black, lacking the shadow level.

No matter whether the photo is black and white or color, only when the exposure is accurate can we get bright colors and rich layering. White photos are overexposed; Dark photos are underexposed. Built-in metering system, designed according to the medium gray reflectivity of 18%, can accurately expose most scenes and restore colors. However, when encountering some special light or scenes, it needs to be corrected on the basis of photometry. If you don't increase the exposure of 1.5-2 when shooting snow scenes, the snow will turn gray; If the exposure of 1.5-2 is not reduced, the black coal will turn dark gray. Because even the most advanced camera has no thinking function, it will only treat all the scenery with medium gray tone with reflectivity of 18%.

8. The photos taken with electronic flash are still underexposed.

There are two reasons: First, the aperture setting is too small. The flash speed of the flash is generally above11000 seconds, and the shutter has lost its light control function, mainly relying on the aperture size to control the exposure. If you take a picture with a flash and there is no automatic shift, you must first calculate the aperture coefficient. Second, the flash power is insufficient. The newly bought flash lamp has to be charged and discharged for more than ten times to make the capacitor in the lamp active before it can be officially used. The old flashlight charging signal lamp only has 70% power, and it can be fully charged in 10 second under normal use.

9. Half of the photos taken by a SLR camera with a flash are black shadows.

This is because the curtain shutter of SLR camera is not synchronized with the flash. SLR cameras take pictures with flash, so pay attention to the synchronization of the flash (the speed of each camera is different).

10, the background of portrait photos is clear and gorgeous, and the characters are embarrassing and dark.

First, backlight shooting uses average metering, which does not add light to people's faces; Second, the background is bright (snow, desert, beach), and the data recommended by internal photometry is used for exposure. The background exposure is moderate and the characters are underexposed. There are three ways to solve this problem: one is to fill characters with flash; The second is to add 1-2 exposure on the basis of photometry; The third is to get close to people and measure the light on the face. After "locking" exposure (using the photometric memory button or changing to manual exposure), return to the original position for composition, focusing and shooting.

1 1, take a group photo, and the surrounding people are incomplete.

There are two situations. First, the head-up camera ignores parallax when shooting, and the picture is too full; Second, although there is no parallax when using a SLR camera, there is no space around the picture. When printing, some pictures are crushed around, and the color enlarger only prints about 95% of the negative. So no matter what camera you use, you should leave some room for composition. Don't let the characters stand on top, fill the picture.

12, the photo has scratches.

If there are scratches on the negative, it may be caused by two things. First, the old cassette used in the large-scale sub-packaging roll was polluted, and sand was caught in the flannel at the film outlet, which scratched the film; Second, the flat plate on the back of the camera has burrs, and the film is scratched by the film. Before using the subcontracted roll, it is best to take the film head back into the film box, carefully clean the flannel at the film mouth with a blowing balloon and a brush, and then take the film head out for later use. If the camera platen has burrs, carefully grind them off with a small piece of No.0 sandpaper (be careful not to scratch the paint film on the platen).

13. The tone of the whole photo is blue.

First, the color temperature is very high. On cloudy or thin clouds, the color temperature of natural light is as high as 7000- 12000K, and the color temperature correction filter is not used; Second, there are dense tree-lined or huge blue advertisements, curtain walls and other environmental reflections. The solution is to use Leiden 85B color temperature reduction filter when shooting. If there is blue ambient light reflection nearby, try to move to an open field to shoot.

14, the tone of the whole photo is orange.

The following three situations may make the tone of a photo red. (1) Use the sunburst film under illumination, without using the Leiden 80B color temperature conversion filter; (2) The color temperature of sunlight in the morning and evening is only 3200K, and low color temperature causes orange-red tone; (3) There are huge red advertisements or red buildings around, reflecting red light.

15, when taking a portrait with a flash, the rear projection is thicker.

In flash photography, if a person is close to the background, there will be a black projection on the background. There are three solutions: first, the characters are far away from the background, so that the projection falls on the ground; The second is to remove the flash and connect it with a flexible cord for horizontal flash shooting; The third is to use light-colored ceiling or wall to shoot with reflective flash.

16, the use of flash, like red eye.

Red eye is easy to appear when flashing in weak light. The reason is that under the dim light, the pupil of the human eye is enlarged, and the strong light of the flash lamp suddenly illuminates, so that the pupil cannot be contracted. When strong light shines directly on the retina, the blood-red color of the visual nerve will appear in the photo, forming a "red eye". There are four ways to overcome it: first, remove the flash lamp and connect it with a flexible cord for lateral flash; The second is to let the eyes of the subject not look directly at the camera lens; Third, before shooting, let the subject look at strong light sources such as electric lights and windows for three minutes or flash once before shooting; The fourth is to use a flash with red-eye prevention function.

17. There are shutter stripes on the TV screen.

China's television system transmits 25 pictures per second. If the shutter speed is higher than 1/30 seconds, shutter streaks will appear. Ordinary cameras shoot TV pictures, and the appropriate shutter is115 seconds.

18, the snow scene is gloomy and the snow is not white.

This is due to underexposure. The ground is highly reflective in snowy days, so the exposure instrument still sets the exposure combination according to the reflectivity of 18%, which will restore the snow scene to a medium gray tone. If the average photometry or partial center photometry is used as the exposure standard, the exposure is insufficient at 1-2 level, and the white snow becomes light gray. The prevention method is to compensate according to the increase of 1-2 exposure (increase of 1-2 aperture or decrease of 1-2 shutter speed).

Seventeen, with a unique shutter speed to describe the dynamic.

An ideal photo showing an athlete's graceful posture should not only have a complete composition, beautiful light and proper tone, but also show the dynamics of the subject wonderfully. And reflect the dynamic is often with some unique shutter speed, its form generally has two kinds:

Solidification dynamics allows readers to watch the thrilling and intense action carefully from the picture. It should take1/250-11000 seconds until the shutter speed is faster. They can clearly record the dynamic body and reveal the whole picture of the dynamic body. When using this shutter speed, the whole world seems to be in a state of solidification, and all the dynamics disappear. The fierce competition will suddenly become silent and the smoke will disperse. People can see all the tiny details in the fierce fighting scene from the photos. The photos taken in this way are mainly not to render the atmosphere, but to be good at analyzing the details (as shown above). Although the picture is still, the splashing waves and the athletes' movements are frozen, we can feel the fierce competition scene and the struggling state of the rowers from the snow-white waves, the athletes' grim expressions and their all-out paddle-holding behavior.

When taking this kind of photos, the shutter speed selected by the camera is related to the speed and direction of the moving object itself. Generally, the required shutter speed can be obtained according to such a simple formula: when the subject enters the viewing range at an oblique angle at a medium distance (10m), multiply the moving speed of the subject by10, and then take the reciprocal of the product (if there is no corresponding speed gear on the camera, you can choose a similar speed gear), which is the required shutter speed. If the athlete's long-distance running speed is 30 km/h, multiplied by 10, and the reciprocal is 1/300, the shutter speed of 1/250 seconds can be used. If the athlete is facing the camera, he can slow down the shutter speed by one step, that is,1125 seconds. If the player passes the ball horizontally, he can get to 1/500 seconds faster.

Performance dynamics

This is to record the athlete's movements with a slow or even slow shutter speed, so that the audience can feel immersive when watching and have a strong sense of movement or speed. At this time, due to the slow exposure of the shutter speed, the background and the athlete's own image will produce stripes to varying degrees, which makes people feel faster (as shown below). Generally speaking, the slower the shutter speed, the more serious the blur and the stronger the motion. Of course, if we can consider the focal length of the lens and the distance between the camera and the subject, the effect will be more remarkable. Usually, the longer the focal length, the closer the distance and the stronger the movement; The shorter the focal length and the farther the distance, the weaker the motion.

When shooting a dynamic subject, it is best to take some static objects as foil in the picture, which can often make the dynamic effect more intense through the contrast between reality and reality.

18. Frequently asked questions? Photometric skills in digital photography

It often happens that some parts in the same picture are bright and some parts are dark, so it is difficult to expose both bright and dark parts normally. No matter how dark or how bright the area is, it will affect the photometric effect of the whole picture. But in many cases, the blue sky and the sea are used as bright backgrounds, or at night as dark backgrounds. We will choose other scenes for comparison. In fact, the effect and purpose we want to achieve are the same, and the operation skills are the same. Let's look at this photo first, which was taken with a camera with average light measurement.

Aperture f/8.0 shutter1125 canon EOS 20d

It is easy to see that the pigeon cage in the middle is dark and has no layers; In order to increase the exposure of the dark part, the viewfinder can completely frame the dark part and take the dark part as the scene of the whole picture. If you measure the light again, you will find the aperture f/8.0 and shutter 1/50(Av takes precedence).

In order to ensure that the level of the bright part is not lost, we take the middle value of these two photometric values, that is, the aperture f/8.0 and the shutter 1/80. (You can readjust the exposure combination according to your personal habits. ) The following figure is obtained from the above operation, which can be compared.

There will be many such situations when shooting. You can decide a certain part of exposure value according to your shooting needs.

19. Skills 】 If it is not enough, you need to make up the lighting skills for indoor portrait shooting.

When taking photos of people indoors, we often use the built-in flash of digital camera to fill the light, but if we can't use the flash light source correctly, it will often leave an ugly shadow behind the main figure, which will seriously affect the beauty of the photos. So, how to avoid or weaken this flash-forward? Keep people as far away from walls or objects as possible. According to the principle of light projection, when people are close to the wall or the object behind them, the original indoor light and natural light can't shine or reflect on the wall and other objects behind them. When the strong light source flashes, the person being photographed will leave a thick flash shadow on the wall and other objects behind him. Therefore, in the case of not affecting the composition, let the characters stay away from the white wall or the objects behind them as far as possible, and keep a certain space and distance, and the flash shadow will be obviously weakened.

When choosing a bright background to shoot indoors, you can use bright doors and windows in natural light as the background, or use existing lighting equipment such as desk lamps to create a bright background for the subject, and choose a suitable shooting angle to make the shadow of the flash disappear in the bright background.

The position of the camera is higher. When the flash is used indoors, the position of the camera should be higher and more upright, so that the projection of the flash will be directly below the person behind you and will be partially blocked by the subject, which will not look so obvious. Try to shoot with your head up or head up as little as possible. In addition, vertical composition should be avoided, because when shooting vertically, the camera should be rotated 90 degrees and the flash is in the side position, which makes it easier for the flash shadow to fall on a certain side of the character, leaving a thick black shadow on the background consistent with the side shadow line of the character. When taking banner photos, the flash light source is emitted from directly above the lens, and the projection is weak.

Proper shielding of flash because the indoor space is small and the shooting distance is close, using flash is not only easy to produce shadows, but also may make people's faces white. At this time, we can use white gauze, stockings and even paper towels to properly shield the flash and make the flash light source softer. When using, stick gauze and other things on the outside of the flash (be careful not to block the viewfinder and focusing hole). If the soft light effect of one layer is not ideal, add two or even three layers. However, after the flash is blocked, the illumination of the flash will decrease, so the exposure value should be increased appropriately.

When shooting indoors in slow synchronous flash mode, besides the light source of flash, there will be natural light and indoor lighting of doors and windows, but the latter two light sources are weak, which can't make the protagonist have enough exposure. We can use the slow synchronous flash mode to illuminate the protagonist with a flash light source, and then shoot other still lifes in the room with a longer shutter (115 ~1sec), so that we can use the original light in the room to weaken the shadow left by the flash. It is best to use a tripod when shooting, or you can fix the digital camera with objects such as tables and chairs to prevent vibration when shooting. At the same time, after the flash is lit, the subject should keep the original posture until the shutter is closed.

Using the reflected light method, for a flashlight with adjustable direction or a digital camera (installed on the top of the machine) that can use an external flashlight, the flashlight cap can be aimed at a white reflector, such as the ceiling and the wall opposite or on the side of the person, and the reflected light source can be used to illuminate the person being photographed. This reflected flash can change the direction of light, from the original front light to the front top light or front side light, which is as natural and soft as scattered light. When using this method, avoid using a colored surface, because its reflected light will project a special color on the photo. The external flash should be placed as high as possible from the top of the camera. The reason for this is to make the flash light illuminate the subject at an angle similar to that of the sun, so that the shadow naturally falls behind the subject without annoying shadows. Of course, this method will also damage the light, so pay attention to the accuracy of exposure.