Camera selection tips: Five criteria to ensure product quality

At present, computers have become an indispensable part of our lives. In order to improve the functions of computers, various manufacturers have also continuously researched and produced peripherals such as printers and scanners. Peripherals and digital products have become more and more popular. Concern and favor. Digital cameras are among the fastest-growing ones.

Today, with the popularity of broadband networks, we can use the camera to see the friends who are far away in the horizon, and truly have the feeling that “the world is closer”. However, many friends do not know much about the camera, so how to choose the camera for their own use?

Five criteria for selecting a camera

Usually, a series of technical parameters can be seen on the outer box of the camera product, such as the maximum resolution, the focus range, etc. What are those places that we should pay attention to?

First, the sensor

This is the heart of the camera, and important things can no longer be important. General camera can be divided into two categories, one is CCD, only a high-end camera to use this sensor, it has the advantages of high sensitivity, anti-vibration, small size, but the price is relatively high; second is CMOS, It has the characteristics of low power consumption and low cost, but its resolution, dynamic range and noise are not satisfactory. In general, CCD imaging levels and quality are higher than CMOS. We recommend that high-end users should first consider the use of CCD sensor products, of course, the price you need to pay a little more.

Second, the pixel

The pixel value is also an important factor to distinguish the quality of a camera. The early digital cameras were basically 100,000-pixel products because the technology level is relatively low and it is currently a product that has been eliminated. Now mainstream products in the market are mostly around 300,000 pixels. With the support of such large pixels, the camera can often play full screen (640×480) when working. When capturing a single picture, it has a unique advantage.

Third, the imaging speed and number of frames

Since the camera is used for web chat, the imaging speed is also very important, and the imaging speed depends on the overall configuration of the camera, so not only a single lens, but also the configuration of other components of the camera determines the quality of the camera. The main part of the camera construction except the lens is the sensor, data processor and peripheral circuits.

The overall configuration if you use poor quality accessories, the lens imaging effect is not good, because it involves the reasonable design of component quality and peripheral circuits, but users often ignore this link, usually blindly seeking the lowest price And ignore the overall performance.

Another factor related to the imaging speed is the number of frames. The number of frames is the number of frames of a picture transmitted in 1 second. It can also be understood as the graphics processor can refresh several times per second, usually expressed in fps. Different screens require different capturing capabilities. The maximum resolution of the mainstream digital camera capture screen is 640×480, but the screen will have a beating phenomenon at this resolution, failing to achieve 30fps capture.

When the resolution is 320×240, depending on the combination of hardware and software, it is possible to achieve the standard rate capture index, so for complete video capture speed, it is only a theoretical indicator. For the frame rate, we can use a book to shake up and down in front of the camera (swing speed not too fast) to see if the image delay is serious? If the image can be basically displayed consistently, it can basically reach the level of 30FPS.

Fourth, focus function is essential

Some users found that the camera was very vague after they bought the camera. When the merchant tried it, it was good. Why did it happen? Generally not caused by the adjustment of coke. Like a point-and-shoot camera, the camera uses a hyperfocal lens, which requires a large depth of field but manual focusing. Therefore, sometimes it is necessary to manually adjust the camera's focal length to get the clearest image.

However, the focal length of many cheap cameras is fixed, that is, the camera can only take a clear image at a fixed distance. Once it is too close or too far, it cannot get a clear image. A good quality camera lens can be adjusted manually by manually adjusting the focal length so that no matter if you put the camera in that position, you can get a clear image by adjusting the focal length. Usually, we can use the adjustment device outside the lens to adjust.

The focusing effect is often measured as the focus range. The focus range refers to the range from the nearest point to the farthest point where the camera can complete focusing. For example, some cameras have an in-focus range of 20cm to infinity, which means that the closest focusing distance is 20cm. Within 20cm, the focusing cannot be completed. Even if the camera can focus, the resulting image is not clear.

V. Data transmission interface

At present, USB has become the standard interface for cameras. This connection method is easy to use, supports hot-swapping, and the device uses its own reserved interrupts. It does not compete for PC resources with other devices. For the camera with 350,000-pixel level, USB1.1 interface transmission rate can fully meet the needs, if you choose a megapixel camera, then the best choice for the USB2.0 interface. However, if you use this type of product in the Internet, the display effect on the network is basically the same as the USB 1.1 product due to the speed of the network.

In addition, factors that users can consider when purchasing a camera include the included software, built-in microphones, angle adjustment, base mounts, and static shooting, all of which can bring us many ease of use. The application program included with the camera is an important part. Many manufacturers have provided some applications such as video e-mail software and simple video editing software, allowing users to choose according to their own situation. “

In addition, some image effect correction and enhancement programs are also very practical. For example, adjusting the camera's color saturation, contrast, edge enhancement, gamma, etc., as long as the appropriate adjustment can make the shooting results have been greatly improved.