How to adjust the sharpness of Canon camera?

Sharpness adjustment method of Canon camera;

1. Application of tripod in shooting.

In many cases, the reason why the photo image is blurred is that the photographer produces "hand shock" or "machine shock" when pressing the shutter. If you use a tripod, no matter how slow the shutter speed is, even if it is exposed for a long time, the image blur caused by "jitter" can be reduced. However, it should be noted that when using the tripod, try to use the cable release, because the vibration generated when the finger touches the shutter may still affect the definition. If there is no cable release, it may be more convenient to use the camera's time-delay shooting function.

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

Although good machines and lenses now have the function of image stabilizer, in the case of hand-held shooting, we should try to use high-speed shutter to shoot. For inexperienced photographers, when the shutter speed is set below 1/30s, the probability of taking photos is greater. Even a professional photographer can't guarantee 100% certainty when shooting with a low-speed shutter. Increasing the shutter speed will correspondingly increase the probability of clear photos. For telephoto, it is recommended to control the shutter speed beyond (1/ focal length). Of course, in order to ensure the brightness of photos, if you use a hand-held camera to increase the shutter speed, it is bound to open a large aperture, thus losing the "large depth of field." However, in order to ensure the clarity of photos, it is sometimes a last resort to give up the depth of field appropriately, or we can comprehensively consider increasing the ISO value to improve the brightness of photos.

3. Make full use of the "best 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 spherical surface of the lens, the light can't focus on the same focus when passing through the center and edge of the lens because of the different refractive indexes, which leads to the decrease of definition. If you shoot with the maximum aperture of the lens, it will lead to the maximum exposure of lens aberration defects, which will lead to the decline of image clarity, while shooting with the minimum aperture of the lens will produce light diffraction and also lead to the decline of image clarity. In order to improve the sharpness reduction caused by aberration, the aperture is usually reduced to improve the imaging quality. Generally speaking, the best aperture of the lens is that the maximum aperture of the lens is reduced by about 2~3 levels.

4. Use the focusing method reasonably.

At present, most cameras have autofocus function. However, if the depth of field is extremely small, autofocus will often be inaccurate, especially if the subject is focused at close range. You should be especially careful when taking close-up portraits with a long focal length lens and a large aperture. If autofocus is used at this time, the "target" must be aimed at people's eyes. If you are not sure, you would rather give up autofocus and use manual focus. Press the shutter half to test whether it is in focus (there is a prompt after focusing), reminding everyone to "start fast and move steadily"! Now some lenses can still be manually focused on the basis of autofocus, so please use them reasonably.

5. Use the hood correctly.

Many people don't care about the use of range hoods. When using front light, front side light or side light, the function of the hood is not obvious. However, when shooting with backlight or side backlight, you must use a hood. Sometimes, even if there is a hood, the sun will still shine directly on the lens, causing the picture to be "red" and produce fog, which will affect the color saturation and clarity of the subject. At this time, the lens angle should be adjusted to avoid direct light. In addition, the hood can also help prevent the lens mirror from being damaged and prevent fingers from touching the mirror.

6. Rational use of depth of field.

The depth of field is determined according to the photographer's shooting purpose. If you are shooting landscape photography, you need a large depth of field to make the clear range of the scene in the photo clear from near to far. If you take a close-up, the depth of field is required to be small, in order to blur the background (or foreground) of the subject in the photo and highlight the subject. How to use depth of field reasonably? Remember: using small aperture, short focal length lens and long-distance focusing shooting has a large depth of field. The depth of field is small by using three methods: large aperture, long focal length lens and close focus shooting. Of course, there are many factors that affect the depth of field, one or two of which can be used, but the effect is more obvious when combined.

7. Try to use low-value sensitivity (ISO).

In order to obtain high-definition images and make photos look rich in texture, in addition to using high-pixel digital cameras and large-format traditional cameras, there is also a simple way to choose low-sensitivity shooting.

Both traditional photosensitive materials and digital image electronic photosensitive elements have a characteristic: the lower the ISO sensitivity setting, the finer the film granularity (the less noise the digital image shows) and the higher the definition of the photo. The higher the ISO sensitivity setting, the greater the graininess of the film (the digital image is noisy) and the definition of the photo is relatively low. At present, the sensitivity of film is in the range of ISO25~ 1600. The ISO sensitivity of digital cameras is designed in different ranges of ISO50~3200 according to the different requirements of manufacturers for low-end, mid-end and high-end cameras. Knowing this characteristic of traditional photosensitive materials and digital image sensing elements, setting ISO sensitivity to a lower value will obviously improve the clarity of photos.

8. Master the correct exposure (photometry) method.

At present, the most commonly used measurement method is center average measurement. Overexposure or underexposure will lead to the decline of image clarity and color cast of the image. To accurately expose, we must master the correct photometric method. When using reflective average metering, sometimes the metering data will lead to inaccurate exposure. For example, if you want to show the snow in winter (snow is the majority in the picture), if you use reflective photometry, the result will be that the snow is not white, but light gray. Experience tells us that in this case, you need to add some exposure to the "accurate" data provided by photometry to make the snow appear "correct" white. On the contrary, you want to represent black coal (coal is the majority in the picture), and the coal is medium gray. At this time, it is necessary to reduce the exposure on the basis of photometry to make the coal look closer to its true color.

In addition, when shooting portraits (with bright background) in backlight, people's faces are often underexposed by using reflective average photometry. At this time, the "light metering" function is used to measure the reflected light of the subject (measuring the human face), and the accuracy of exposure is beyond doubt.

9. Choose the storage format of RAW images as much as possible, and reserve space for post-processing, so as to facilitate the post-processing software to adjust the sharpness of photos.

RAW is a lossless compressed file storage format, which can completely record all kinds of related parameters at the moment of shooting, including the original data such as camera, lens, focal length and exposure combination.

Compared with TIFF format, the biggest advantage of RAW format is that the storage space is smaller than TIFF format. Although TIFF format is a lossless compressed file format, and photos can be printed directly without converting the file format, TIFF format takes up a lot of storage space. Take photos of the same quality, using RAW format is 2~3 times more than TIFF format, or even more. Therefore, it seems reasonable that some manufacturers no longer use TIFF format on cameras.

Compared with JPEG format, the quality of RAW format is obviously better than JPEG format (the bigger the photo, the more obvious it is). Because JPEG format is a lossy compressed file format, and it cannot be recovered after compression. If the JPEG file is changed every time, it is still saved in JPEG format and compressed again, resulting in the image being damaged again. Therefore, JPEG files should be saved once after all editing. It is best not to take photos in JPEG format for enlarged size. However, JPEG format still has advantages, such as low file speed, large number of files, strong compatibility and convenient transmission through the network.

10, make full use of the machine's own setting function.

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

Friendly reminder: the internal settings should be set according to the lens, scene and shooting requirements, not the only fixed value, and setting the parameters to the limit value is not necessarily the most appropriate value.