General Methods to Improve photo quality

 

1. Use a tripod whenever possible

In many cases, the reason for blurred and unclear photo images is that the photographer produces a "Hand vibration" When pressing the shutter or a "machine vibration" when the camera reflector is raised. If a tripod is used, no matter how slow the shutter speed is set, or even prolonged exposure, it can prevent Image Blurring due to image jitter. However, when using a tripod, try to use the shutter as much as possible. Ignoring this, there is still a possibility that the vibrations produced when the fingers reach the shutter may affect the definition. Another method is to use the timed selfie function to take portraits or scenes. Generally, the shortest time is set so that the captured objects will not be too tired.

2. Use high-speed shutter whenever possible

When taking a photo with a camera in hand, use a high-speed shutter whenever possible. When an inexperienced photographer sets the shutter speed below 1/30 s, the probability of a photo being blurred is high. Even professional photographers cannot be sure to take a shot at a low speed. Increasing the shutter speed will increase the probability of photo clarity. Of course, when a hand-held camera increases the shutter speed, it is bound to open a large aperture and thus lose the "large depth of field". However, to ensure the clarity of the photo, giving up the depth of field is a last resort. Another common mistake is that when the shutter is pressed, the hand is suddenly raised, which produces a very high vibration. It is better to press the shutter and wait until the shooting is complete.

3. Try to use "optimal aperture"

There are different degrees of imaging errors in any lens, which will affect the imaging quality of the lens to varying degrees. Due to the different curvature of the lens sphere, the light passing through the center and edge of the lens cannot focus on the same focus due to different refractive indexes, resulting in decreased clarity. For example, shooting with the maximum aperture of the lens will cause the maximum exposure of the lens's distortion defect, resulting in reduced image clarity. Shooting with the minimum aperture of the lens will produce diffraction of light, this will also cause image clarity to decrease. To improve the quality of imaging, aperture reduction is usually used to improve the quality of imaging. Generally, the optimal aperture of the lens is the maximum aperture of the lens, which is reduced by 2 ~ About 3 files, the photographer can compare the optimal aperture of a certain lens. It should also be noted that the effect of aperture on depth of field is that the larger the aperture, the smaller the depth (the more obvious the Blur ).

4. Use manual focus whenever possible

Currently, most cameras have auto focus functions. However, when the depth of field is very small, auto focus tends to focus less accurately, especially when focusing closely at the main body and using a long focal length lens and using a large aperture to take close-up portraits, be especially careful. If auto focus is used at this time, the "target" must be on the eyes of the character. If you are not sure about it, you 'd rather give up auto focus and use manual focus. People do not want their ears or noses to be clear, but their eyes are blurred.

5. Try to use the hood

Many people do not care about the use of the hood. When front light, front light, or side light is used, the effect of the mask is not obvious. However, you must use a shadow when shooting back-to-light or side-to-side backlight. Sometimes, even if you use a shadow, the sun will still direct to the camera, causing the screen to "light" and produce smog, affects the color saturation and clarity of the subject. At this time, the lens angle should be adjusted to avoid direct light on the lens. In addition, the shadow helps prevent the lens from being damaged and prevents the finger from touching the mirror.

6. make proper use of depth of field

The depth of field is determined based on the photographer's shooting purpose. If you are shooting landscape photography, you need to increase the depth of field, in order to make the clear range of the scenery in the photo from near to far clearly. If a close-up is taken, the depth of field must be small to blur the background (or foreground) of the subject on the photo to highlight the subject.It is counterproductive to use a small depth of field to show the scenery theme, or use a large depth of field to show the close-up of the subject.The general practice is: small aperture, short focal length lens, long-distance focus shooting three methods, the depth of field is large. The large aperture, long focal length lens, and close-range focus shooting methods are used, and the depth of field is small. Either of the two shooting methods can be used, but there are no three methods for the effect.

7. Use low-value sensitivity as much as possible

To obtain the high definition of an image and make the photo look rich in texture, in addition to choosing a high-pixel digital camera and a large-frame traditional camera, there is also a simple way, select low sensitivity.

Traditional Photosensitive Materials and digital image electronic sensing components have the following characteristics: the lower the ISO sensitivity, the finer the granularity of the film (the less noise the digital image shows ), the image definition is relatively high. The higher the ISO sensitivity, the higher the granularity of the film (the greater the noise of digital images), and the lower the image quality. Currently, the sensitivity of the film is in ISO25 ~ 1600 range options; digital camera ISO sensitivity, root manufacturers for low-end, mid-end, high-end cameras of different requirements, designed in ISO50 ~ 3200. I learned about this feature of traditional Photosensitive Materials and digital image sensing components. When taking a photo, I set the ISO sensitivity to a low value, and the quality of the photo will be significantly improved.

8. correct exposure (metering) Methods

Over-exposure or under-exposure results in decreased image clarity and image color offset. For accurate exposure, you must master the correct method of light measurement.

When the reflective average light measurement is adopted, sometimes the exposure is inaccurate due to the metering data. For example, if you want to show the snow in winter (the majority of white in the screen), such as the reflection light measurement, the shooting results, the snow is not the original white, but a light gray color, experience tells us that in this case, we need to add some exposure to the "accurate" data provided by the light measurement to make the snow "correct" White. On the contrary, if you want to show the black coal (the majority of coal on the screen), as a result, the coal is medium gray, then you need to reduce some exposure on the basis of the light measurement, so that the coal looks closer to the true color.

In addition, when a portrait (with a bright background) is taken in the reversed light mode, the average light metering method is adopted, and the facial exposure of the person is often insufficient. Of course, there is no doubt that the accuracy of the exposure is accurate when you use a camera with the "spot metering" function or a metering table with the "spot metering" function to test the reflected light of the subject (to measure the face of the person.

The principle of incident light measurement is that the metering table directly measures the illuminance of light on the subject. Therefore, no matter whether the subject is a gray, black, or white object, the results of the incident light measurement are as follows, can correctly reflect the original tone and color of the subject (which is better than the reflective average light measurement ). However, when measuring the incident light, you must note that the metering table must be moved to the position of the subject to measure the light. At the same time, the bra center on the metering table must be directed to the photographic lens.

9. properly set White Balance

One of the important reasons is the color temperature deviation. The color temperature of white light is 5500 K. If the color temperature is lower than this value, the light is red. The lower the color, the more red the color temperature is. When using a traditional camera, the color temperature is controlled by selecting "daylight type" film or "light type" film or using a variety of color temperature filters.

A digital camera can directly control the white of the color temperature on the menu. The principle is to use the partial color light to remove the neutral color light to achieve the purpose of white light. There are generally three types of White Balance Functions for the camera: ① Preset white balance (Preset); ② Automatic white balance (Auto); ③ Manual white balance (Manual ).

If the color temperature of the light source does not change much and is clear, such as sunlight, cloudy days, incandescent lamps, fluorescent lamps (divided into fluorescent lamps, warm fluorescent lamps, and cold fluorescent lamps), then, you just need to go to the "check" in the "preset white balance. If the color temperature of the light source changes rapidly, such as the weather in clear or dark conditions, the rapidly changing stage lighting will make the photographer unable to adapt. In this case, the "Automatic white balance" should be used ".

If the light source is mixed light or the color temperature value is very high or very low, "Automatic white balance" cannot be used. In this case, the best way is to use "manual white balance ". The method is to place a blank sheet of white paper in the light of the shooting object, align the lens with the White Paper, fill the screen, and follow the instructions of "manual white balance" in the camera menu, after setting, you can take a picture. This manual white balance is only valid under this type of light source. For other light sources, you need to reset the white balance according to the above method.

Interestingly, using the White Balance's complementary color principle can achieve some unexpected artistic effect. For example, if you want to take a picture in the sun, you can set the "incandescent" mode of white balance and the "Cloudy" mode of white balance. If you want to achieve more colors, you can use "manual white balance" to set it by yourself. For example, if you use a blue paper preset, the screen effect is yellow. If you use a blue paper preset, the screen effect is red, and so on. You can also open the Photoshop Graphics Software, select or prepare the desired "complementary colors" (Thousands of colors), and store them in "manual white balance" for backup, if you are interested, try it.

10. Try to use RAW image storage format

RAW is a lossless file storage format. It can take a variety of related parameters at the moment of shooting, including cameras, lenses, focal lengths, and exposures.

Compared with the TIFF format, the RAW format has a smaller storage space than the TIFF format. Although the TIFF format is a lossless compression file format that can print photos directly without converting the file format, the TIFF Format occupies a large storage space. Take photos of the same quality. Take two more photos in RAW format than in TIFF format ~ 3 times the number or even more. Therefore, some manufacturers do not use the TIFF format on their cameras. It seems reasonable.

Compared with the JPEG format, the RAW image quality is obviously better than the JPEG format (the larger the photo is, the more obvious ). The JPEG format is a lossy compression file format and cannot be recovered after compression. If each change is made to a JPEG file, it is still stored in the JPEG format, and the image is damaged again. Therefore, a JPEG file should be saved once after all edits are completed. You are advised not to use JPEG format to take large-sized photos. However, the JPEG format still has the advantages of Fast File speed, large number of sheets, strong compatibility, and network transmission.

11. Use the flashlight well

① Use the reflection flash method as much as possible. The reflection flash is to reflect the flashlight to the ceiling and walls or reflector. The advantage of reflective flash is that the light is uniform, natural, and shadow is soft. Note the following when using: 1. when using manual flashing, note that the "camera distance" in the formula of "Flashlight index camera distance = aperture coefficient" refers: the sum of the distance from the flashlight to the reflection object plus the distance from the reflection object to the subject. 2. Pay attention to the optical common sense of "the angle of incidence is equal to the angle of reflection", and master the angle of the flashlight. 3. If the room is too small, avoid reflection to the ceiling. Otherwise, the shadow of the eye and nose may occur. You can shoot at the wall or reflector. 4. The reflector must be white. Otherwise, the color temperature of the flashlight will be changed to make the subject partial.

② The diffuse flash method is to directly add the milky white soft film and the white handkerchief or gauze on the flashlight (haha, of course, it can also be a white silk so) and so on, flashing to the subject. This flash can produce soft light effects. Due to the fading of the fabric on the flashlight, the slow-shot flash method needs to increase the aperture coefficient or reduce the camera distance to compensate for the flash loss.

③ When shooting a person with a night scene with a flashlight, you must use a tripod for night scene shooting. The Background Brightness cannot be solved by the flashlight. If the intensity of the flashlight is increased, the facial exposure of the person will be excessive, the background is still dark. The secret of using a tripod is the shutter speed, which is generally determined by the brightness of the background. Because the light in the night scene is generally dark, the exposure becomes ineffective, at this moment, the shutter time is set to 1 s or 2 s, and the photosensitive density is not much different. After determining the exposure speed of the background, you can place the person to the specified position for shooting. the aperture coefficient can be calculated based on the above formula, for example, the flashlight index is 32, the shooting distance of a person is 4 m. After calculation, the aperture coefficient is F8. After such an exposure combination, the brightness of the person is appropriate and the Background Brightness is also displayed.

④ When a portrait is taken in an outdoor backlight and the flashlight is used for manual lighting, the circle value should be determined based on the shooting distance (or the shooting distance should be determined based on the aperture coefficient ), if the aperture coefficient is too large or too small (the camera distance is either far or near), the correct impression of the portrait will be affected.

⑤ When shooting with an ultra-wide angle lens, pay attention to the overhead of the external flash. There are many flash models, but they all specify the focal length range for each model. For example, only 24 ~ The flashlight used within the focal length of the 105mm lens indicates that there is no problem with the flashing coverage force when the 24mm lens is used; however, a wider angle lens is used, this flashlight may have insufficient coverage. It shows that the center of the photo is normal, the surrounding area or four corners are black, and the edge and center of the photo are uneven. There are two solutions: one is to use the wide-angle extension film that comes with the flashlight (some flash comes with it), and the other is to use the reflection flash method, it can effectively solve the problem that the flashlight does not cover the wide angle lens.

12. Make full use of computer-modified photo Defects

Shooting-when an error occurs, you can use a computer to perform post-repair. Before the advent of the digital scanner, the photo modification and "face change" were completed in the dark room, which was difficult and had a low success rate. With the rapid development of digital technology, this problem becomes simple and easy. In today's world, whether it's a negative, reverse, or digital image file, you can enter your computer and use the image editing software for modification or creative processing.