Traditional Culture Encyclopedia - Photography and portraiture - Significance and Function of Digital Camera Parameters

Significance and Function of Digital Camera Parameters

(A) About ISO

ISO setting adjustment is mainly affected by two aspects, the first is the trouble of insufficient light, and the second is the problem of slow shutter speed.

If you have a tripod or can guarantee a digital camera to shoot regularly, you can shoot by increasing the aperture shutter or slow shutter. However, if there is no tripod support or a handheld digital camera can't guarantee stable shooting, you must choose a higher ISO.

The adjustment of ISO should be carried out step by step. First move to the nearest gear to see if you can achieve your shooting intention. If it's not ideal, move it up one notch, so as to ensure the best ISO setting for shooting.

The increase of ISO setting will bring about the increase of noise. Of course, in the case of poor lighting conditions, the increase of ISO can improve the shutter speed and realize the reliability of shooting.

(B) About white balance

White balance control is to make the color of photos taken under various light conditions completely consistent with the color of the scenery seen by human eyes through image adjustment. White balance is a function that defines "white" as "white" regardless of the ambient light, which can ensure the accuracy of color reproduction.

When fully automatic mode is adopted, our easy-to-use digital camera will also adopt automatic white balance. Error-prone under special circumstances. It is recommended that you call the preset white balance value in the digital camera. After setting the white balance correctly, the color performance is more natural than that on the right.

Mastering the white balance, the photos will have accurate color performance.

(3) About exposure compensation

Concept of exposure compensation (EV): Photography is actually a process in which a photographer uses his own photography technology to calculate the ambient light and capture the scene image through photographic equipment.

This process is related to the aperture value of the device (controlling the luminous flux entering the camera per unit time), shutter speed (exposure time) and ISO (sensitivity to light). In the Gao Fancha environment with complex light and strong contrast, the photos taken by P (program automatic exposure) block are often unsatisfactory and the effect is not the best.

At this time, the photographer needs to manually adjust the exposure parameters of the equipment, that is, the exposure compensation EV (exposure value). There are many ways to compensate and adjust the light, such as flash lamp, photographic lamp and reflector. Adjustment of aperture value and compensation of luminous flux parameters for exposure time.

Correctly adjust the EV value: use EV+ in typical underexposed scenes (objects have many bright areas, such as backlight, water surface under strong light, snow scene, sunrise and sunset scene, etc. ).

EV- Used in typical overexposed scenes (dark areas with many objects, such as dense forests, objects in shadows, close-ups of black objects, etc. ). Simply put, it is "white plus black minus, bright plus dark minus".

Extended data:

Data storage of digital camera;

The audio and video storage formats of digital cameras are roughly as follows.

1.AVI: Audio and video formats and extensions. AVI is one of the earliest popularized specifications. Because the AVI format has not been reduced, AVI video files in just a few tens of seconds often need 5 ~ 8 MB of storage space.

Because there is no complete set of specifications for manufacturers using AVI format to refer to, there are at least more than 100 specifications derived by a single company.

2.MOV: MOV is one of the most commonly used animation formats for most digital camera manufacturers. The main reason lies in its simplified compression technology, which provides users with good audio and video selection at low resolution.

3.Motion JPEG-AVI: Because JPEG adopts the full-color image standard, it adopts the unique distortion compression technology DCT, which removes the unimportant parts of the image data and effectively reduces the file size.

4.MPG: With the increasing popularity of VCD, even the technology of MPEG- 1 is popularized. Although, only a few digital cameras can support this specification of animation recording (mostly Sony in Japan).

The full name of MPEG is moving picture expert group, which belongs to ISO/IEC standards (International Organization for Standards and International Electronic Technology Association).

MPEG- 1 technology can fast forward, rewind and even select time points for long-time electronic images by decoding playback programs. Files recorded by MPG can also be directly recorded on VCD and watched by VCD player.

5. ASF: The feature of ASF format is that the image part adopts the latest MPEG4-4 compression method, and the sound part uses its own WMA format.

WMA emphasizes that its compression ratio is more than twice that of MP3, and its sound quality is similar to MP3. In addition, WMA's confidentiality provisions and design right documents are not as easy to copy as MP3.

6.RM: RealVideo is a real-time playing software specially developed by RealNetworks for network audio and video, which allows web page producers to provide real-time audio and video programs on the website.

Users can go to the following website to find the software and information for downloading RealPlayer for free. RM also supports online streaming direct playback without downloading the entire audio and video file.

7.GIF animation format: Strictly speaking, GIF can only be regarded as a dynamic picture display format. The color can only support 256 levels, so it cannot be recorded.

The standard specifications are also divided into GIF87a and GIF89a, and only GIF89a has transparent background and animation playback capability. In the application of digital cameras, Sony is the only one that can directly make GIFFIClip.

References:

Digital camera-Baidu encyclopedia