How to adjust the sharpness of Canon camera?

Canon camera sharpness adjustment method:

1. Use a tripod when shooting.

In many cases, the reason why the photo image is blurry and unclear is that the photographer produces "hand shake" or "machine shake" when pressing the shutter button. If you use a tripod, no matter how "slow" the shutter speed is set, or even a long exposure, you can reduce image blur caused by "shake". But be careful, when using a tripod, use a shutter release cable as much as possible, because the vibration generated when your finger touches the shutter may still affect the clarity. If you don’t have a shutter release cable, you can use the camera’s time-lapse shooting function, which may cause More convenient.

2. According to the actual shooting situation, use a high-speed shutter as much as possible.

Although good machines and lenses now have functions to prevent shake, when shooting handheld, use a high-speed shutter as much as possible. For inexperienced photographers, when the shutter speed is set below 1/30s, the probability of taking blurry photos is high. Even professional photographers cannot guarantee 100% certainty when shooting at low shutter speeds. Increasing the shutter speed will correspondingly increase the probability of photo clarity. For telephoto, it is recommended to control the shutter speed beyond (1/focal length). Of course, in order to ensure the brightness of the photo, when the shutter speed is increased while holding the camera, the aperture will inevitably be opened wider, thus losing the "large depth of field", but for To ensure the clarity of the photo, sometimes giving up the depth of field is a last resort, or you can consider it comprehensively and increase the brightness of the photo by appropriately increasing the ISO value.

3. Make full use of the "optimal aperture".

Any lens has varying degrees of imaging errors, which will affect the imaging quality of the lens to varying degrees. Due to the different curvatures of the spherical surface of the lens, light cannot focus at the same focus due to different refractive indexes when passing through the center and edge of the lens, resulting in a decrease in clarity. If you shoot at the maximum aperture of the lens, the aberration defects of the lens will be exposed to the greatest extent, resulting in a decrease in image clarity. If you shoot with the minimum aperture of the lens, light diffraction will occur, which will also lead to a decrease in image clarity. In order to improve the problem of reduced sharpness caused by aberration, narrowing the aperture is usually used to improve the quality of the image. Generally speaking, the optimal aperture of a lens is about 2 to 3 stops smaller than the maximum aperture of the lens.

4. Use focusing methods rationally.

Most cameras today have an autofocus function. However, when the depth of field is particularly small, autofocus will often focus inaccurately. Especially when focusing close to the subject, using a long focal length lens, and using a large aperture to shoot close-ups of portraits, you must be particularly careful. If you use autofocus at this time, the "target" must be aimed at the person's eyes. If you are not very sure, you would rather give up autofocus and use manual focus. You can test whether the focus is achieved by pressing the shutter halfway (after achieving focus, there is Alert sound), and remind everyone to "start quickly and move steadily"! Nowadays, some lenses can still focus manually on the basis of autofocus. Please use them rationally.

5. Use the hood appropriately.

Many people don’t care about the use of lens hoods. When using front light, front side light or side light, the role of the hood is not obvious. However, when shooting with backlight or side backlight, you must use a hood. Sometimes, even if you use a hood, sunlight will still shine directly on the lens, causing the picture to "blow out" and produce fog, which affects the color saturation and clarity of the subject. Spend. At this time, the lens angle should be adjusted to avoid direct light hitting the lens. In addition, the lens hood also helps prevent damage to the lens mirror and prevents fingers from coming into contact with the mirror surface.

6. Make reasonable use of depth of field.

The depth of field is determined by the photographer’s purpose of shooting. If you are shooting landscape photography, the depth of field needs to be large. The purpose is to make the clear range of the scenery in the photo clear from near to far. If you are taking a close-up, the depth of field needs to be small. The purpose is to blur (blur) the background (and possibly the foreground) of the subject in the photo and highlight the subject. How to use depth of field reasonably? Remember: using three methods of shooting with a small aperture, a short focal length lens, and a long-distance focus will increase the depth of field. Using three methods: large aperture, long focal length lens, and close focus shooting, the depth of field will be small. Of course, there are many factors that affect the depth of field. You can also use one or two of the shooting methods, but the combined effect will be more obvious.

7. Use as low a sensitivity (ISO) as possible.

To obtain high-definition images and make photos look rich in texture, in addition to choosing to use high-pixel digital cameras and large-format traditional cameras, there is an easy way, that is, to choose low-definition cameras. Sensitivity shooting.

Traditional photosensitive materials and digital image electronic sensing elements have a characteristic: that is, the lower the ISO sensitivity is set, the finer the grain size of the film (digital images show less noise), and the quality of the photo The clarity is relatively high. The higher the ISO sensitivity is set, the greater the graininess of the film (digital images appear to be more noisy), and the photo clarity will be relatively low. Currently, film sensitivities are available in the range of ISO25~1600; the ISO sensitivities of digital cameras are designed in different ranges of ISO50~3200 based on the different requirements of manufacturers for low-end, mid-range and high-end cameras.

After understanding this characteristic of traditional photosensitive materials and digital image sensing elements, when taking photos, setting the ISO sensitivity to a low value will significantly improve the clarity of the photos.

8. Master the correct exposure (metering) method.

Nowadays, the most commonly used metering method is central average metering. Overexposure or underexposure will cause image sharpness to decrease and image color to shift. To accurately expose, you must master the correct metering method. When using reflective average metering, sometimes pressing the metering data will result in inaccurate exposure. For example: If you want to show the white snow in winter (white snow accounts for the majority of the picture), if you use reflective metering, the shooting result will be that the white snow is not the original white, but appears in a light gray tone. Experience tells us that in In this case, it is necessary to add some exposure to the "accurate" data provided by the photometer in order to make the snow appear "correctly" white. On the contrary, you want to express black coal (coal accounts for the majority of the picture). As a result, the coal appears medium gray. At this time, you need to reduce the exposure based on the metering to make the coal look closer to its true color.

In addition, when shooting portraits in backlight (with a bright background), using reflective average metering, the faces of the people are often underexposed. At this time, use the "spot metering" function to measure the reflected light of the subject (measuring the person's face). There is no doubt about the accuracy of the exposure.

9. Use RAW image storage format as much as possible to reserve space for post-processing so that you can adjust the sharpness of the photo through software later.

RAW is a lossless compressed file storage format that can completely record various relevant parameters, including the most original data of the camera, lens, focal length, exposure combination, etc., at the moment of shooting.

Compared with TIFF format, the biggest advantage of RAW format is that the storage space is smaller than that of TIFF format. Although the TIFF format is a lossless compressed file format and photos can be printed directly without converting the file format, the TIFF format takes up a large amount of storage space. To take photos of the same quality, the number of photos taken in RAW format is 2 to 3 times or more than in TIFF format. Therefore, it seems reasonable that some manufacturers no longer use the TIFF format on cameras.

Compared with JPEG format, the image quality of RAW format is obviously better than that of JPEG format (the larger the photo, the more obvious it is). Since the JPEG format is a lossy compressed file format, it cannot be recovered after compression. If a JPEG file is modified every time, it is still stored in JPEG format and compressed again with loss, causing the image to be damaged again. Therefore, a JPEG file should be saved once after all editing is completed. When placing larger-sized photos, it is best not to take them in JPEG format. However, the JPEG format still has advantages, such as small files, high speed, large number of images, strong compatibility, and easy transmission through the network.

10. Make full use of the machine’s own setting functions.

Nowadays cameras have various parameter setting functions. You can choose appropriate parameter settings according to your own needs and give full play to the characteristics of the machine. Generally, SLR digital cameras have photo style settings: sharpness, contrast, saturation and hue.

Friendly reminder: The in-camera settings should be set according to the lens, scene, shooting requirements, etc. They are not the only fixed values, and setting the parameters to the extreme values ??may not necessarily be the most suitable values.