What parameters do you mainly look at when buying a camera? !

Buying a camera mainly depends on the size, type, aperture size, focal length, pixels and other parameters of the photosensitive element.

Detailed analysis:

1. The size of the photosensitive element generally ranges from11.6 inches to 1/2.5 inches, and the larger the better, that is,11.6 is good, but the price is certain.

2. The types of photosensitive elements, CCD CCD and COMS, have their own advantages, but now the latter is more common, mainly in dark light. CCD has better details in the case of sufficient light, but its structure is complex, so it has no advantage in the small photosensitive element of card machine. Fuji's superCCD technology is special and not bad. Except fuji, CCD is not considered.

3. Aperture size, if the maximum aperture of the card machine can be around F2.0, it will be very good, and F 1.8 is even better, which is very useful in dark light and has a certain background blur effect. Of course, a large aperture is expensive.

4. Focal length, some cameras only have a focal length of 3 times or 2.5 times, and some just simply focus, that is, they can't zoom. This is not to say that it is not good. It may be because the size and aperture of the photosensitive element mentioned above are taken care of, and the distortion at both ends is difficult to control when the zoom range is large. The zoom range is small or fixed because the lens structure is simple and the photo quality is higher. This is only for people, to see if you need a large zoom (large zoom card machine usually has a small photosensitive element due to structural restrictions). Fixed focus is expensive and inconvenient, but the general lens quality is very high. Don't blindly pursue large zoom.

5. More than100000000 pixels is enough for the card machine, but the bigger the better. In the same size photosensitive element, the larger the pixel is, the smaller the area of each pixel is, and the less light is received, which affects the imaging effect. 100000 to140000 is very suitable, so it is not surprising to see that an expensive camera has only100000 pixels, in pursuit of the previous indicators.

The main parameters to look at when choosing a machine are lens and CCD, which are the key components of a digital camera and cannot be ignored.

Digital camera selection guide-lens selection

Among the physical components of digital cameras, the lens is a very important one, and its quality is the key factor affecting the image quality. In the purchase of digital cameras, lens material, focal length and zoom ability are three main parameters. At present, the lens materials of digital cameras are mainly glass and plastic.

Although the image projected by all-glass lens is the clearest, it doesn't mean that the camera with glass lens is necessarily better than the plastic one. This is because optical imaging is quite complicated, which is influenced by the design of lens group to some extent. Moreover, glass material is heavier than plastic material, which may also affect the overall weight of the camera. So when you buy a glass lens, don't think that it has absolute high quality, but also make a comprehensive observation from many aspects.

In the technical specifications of digital cameras, the parameter of focal length is generally marked as F value (representing the maximum aperture) and F value (representing the focal length). The focal length usually includes the design value of the camera itself, which is equivalent to the focal length value of an ordinary 35mm camera, such as f=8 to 24, which is equivalent to 38- 1 15mm of the 35mm camera.

Generally speaking, a 35mm standard lens is 28-70mm. If it exceeds 70mm, it means that the lens has telescopic function; if it is less than 28mm, it has wide-angle effect. At present, most mid-range digital cameras have optical zoom lenses, but the zoom range is very limited, rarely exceeding 10 times, so such cameras can generally be equipped with telephoto lenses and filters. Some digital cameras also have digital zoom function, which can expand the zoom range again, but you should pay attention that digital zoom only enlarges the pixels, and the actual optical resolution has not changed at all.

For the zoom lens, the general household digital camera can zoom 2 ~ 3 times. In fact, for the zoom function of digital cameras, the zoom lens is not necessarily better than the fixed focus lens at a certain price. Because the design of zoom lens is complicated, it will be inconsistent in each focal length segment, while the design of fixed-focus lens is much simpler and performs very well in a fixed focal length segment. In addition, my personal opinion is that the product quality of traditional professional camera manufacturers is better.

Guide to digital camera purchase-CCD and LCD purchase

? Photosensitive imaging element

Generally speaking, the imaging system of digital camera includes four parts: lens, aperture, shutter and photosensitive imaging device, among which photosensitive imaging device is the core component and the most expensive one, which can be called the heart of digital camera. At present, the photosensitive elements of digital cameras mainly use two kinds of photosensitive elements: CCD and CMOS. Compared with CMOS, under the same pixel, CCD consumes a lot of power and is expensive, but the image quality produced by CCD photosensitive devices is much better, so it has become the mainstream of the market. We mainly introduce a digital camera with CCD as imaging device.

There are two kinds of CCD: area CCD and scanning linear CCD. The CCD chip of area CCD digital camera has the advantage of fast shooting speed, which can shoot moving scenes and adapt to the environment with flash. The resolution of CCD chip used in scanning linear CCD digital camera is extremely high, but due to the scanning process, the higher the resolution, the longer the exposure time is required, which leads to the inability of this kind of digital camera to shoot moving scenes or flashlights. Therefore, unless it is only used for still life shooting, you should generally choose an area CCD digital camera.

Regarding CCD, an important parameter used to distinguish the grade of digital camera is "pixel value", which depends on the number of photosensitive elements on the CCD chip. The more numbers, the higher the resolution of the image and the higher the quality of the photos taken. So when you buy a digital camera, you must remember that you can only use CCD pixels to measure the quality of a digital camera, but not other indicators.

In addition, we can often see that CCD is expressed by fractions, such as 1/2 inch CCD, 1/2.7 inch CCD. From the actual shooting effect, the imaging quality of digital camera using small chip CCD is relatively good. This is because the smaller the chip area, the higher the integration, and the CCD with high integration is generally better in raw materials and technology.

liquid-crystal display

At present, most digital cameras have color LCD screens, which are usually 1.8 inch or 2 inch for viewing, previewing and deleting photos. Some models can provide a visual experience as large as a 2.5 inch LCD screen. Although you can get many benefits of viewing, previewing and deleting images at any time through LCD, it also brings some inconvenience, because it is a very power-consuming device on digital cameras, and four ordinary batteries can only image about 15 (turn on LCD or use LCD to see the results after shooting), so the investigation of LCD is mainly about its energy saving.

At present, some digital cameras use energy-saving lighting LCD screens to display images by collecting external light sources. Although the brightness of this LCD screen is poor, it reduces the energy consumption, greatly prolongs the service life of the battery and saves the cost, so you'd better choose this LCD digital camera when purchasing.

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