Characteristics of digital cameras

When shooting, users can watch the moving image to be shot through the LCD screen of DV, and they can see the shot moving image immediately after shooting. Through DV, the captured moving images can be converted into digital signals and stored in DV band together with the sound signals recorded by the microphone.

DV can be connected to a computer, read the contents of the DV tape, and then post-process these contents, such as editing, or carve them into VCD or DVD for storage.

DV can also be connected to a TV, which can not only read the contents of DV tapes, but also record TV programs. The market is dominated by seven manufacturers: Sony, Panasonic, JVC, Canon, Samsung, Sharp and Eptek, among which Sony accounts for half of the country. Sony is in the leading position in the fields of traditional tape DV, brand-new DVD digital camera and HDV.

Of course, the products of the seven major brands are of good quality and have different functions. Each manufacturer's products have their own characteristics. This must be chosen according to the individual's own needs. 1. Charge coupled device. The pixel of CCD is an important index to measure the imaging quality of digital camera. Pixel size directly determines the clarity, color and smoothness of the captured image. The pixel of CCD basically determines the grade of digital camera. Now most cameras are 800,000 pixels, 6.5438+0.07 million pixels. However, now the overall pixel is improving, and there are more and more cameras with 2 million and 3 million pixels. The area of CCD is also an important index. The imaging quality of small area CCD is relatively blurred, and the richness of color reproduction is also poor. Moreover, the area used for anti-shake is much smaller, and the anti-shake function is of course weak. At present, Sony, Panasonic and other brands in the market have launched 3 million pixel products.

2.CMOS .CMOS is a brand-new sensor besides CCD. This is the first time Sony has applied it to digital cameras this year. At present, it is only used for Sony DCR-PC 1000E and HDR-HC 1E high-end cameras. Compared with CCD, CMOS has the advantages of fast transmission rate, low power consumption and wider dynamic image range. It should be said that CMOS has more advantages than CCD in promoting the popularization of HDV.

3. Is the pixel as high as possible? At present, the pixel of digital camera consumer products has reached 6.5438+0.02 million, while the pixel of camera products is only about 3 million. The higher the pixel, will the picture quality be clearer? This view is obviously untenable. Because the dynamic pixel of CCD image sensor is the key to determine the imaging quality of a product.

When shooting dynamic images, the highest resolution that a home digital camera can achieve is only 720X576dpi, beyond which DV format cannot be supported. Due to the limitation of its own technical bottleneck, there is not much difference in the substantial imaging quality of products above 400 thousand pixels. At present, the resolution of TV screens used by ordinary families in China is less than 400,000 pixels, and no matter how high the dynamic pixels of your digital camera are, when playing on TV or recording on DV tape, the dynamic effective pixels are generally around 400,000 pixels, so you don't have to blindly pursue the high pixel number of the digital camera image sensor. Therefore, when ordinary consumers choose digital cameras, about 100 pixels can completely meet the demand, and products with more than 2 million pixels are not of great practical significance in actual dynamic shooting.

4. Can have 4 camera functions. Is DV equivalent to a digital camera? Although "one camera can be used for two purposes" is a development trend of digital camera products, the current level of technology is not enough to achieve the perfect integration of the two cameras. Many products only meet the requirements on CCD pixels, but no matter how good they are, they can't compare with real digital cameras, and the photo-taking effect can't compare with real digital cameras. Although some high-pixel DVs can improve their shooting clarity to a certain extent, there is still a big gap compared with digital cameras in image level and color. High-pixel CCD sensor does improve the static shooting ability of digital camera to some extent, but there is still a big gap with digital camera in imaging effect. Heavy graininess, lack of layering and dull color are the shortcomings of digital camera static shooting, and three or four million pixels can't avoid this problem. In addition, high-pixel digital cameras are expensive, so the cost performance is not high.

Therefore, it is enough for ordinary families to use a machine with about 800-/kloc-0.0 million pixels for daily family photography, and there is no need to spend thousands of dollars to pursue high-pixel photography. For home digital cameras, we mainly use them as digital cameras. There is no need to demand such a high still image effect. If you have a high demand for still photos, it is more appropriate to buy a digital camera. 1. Like digital cameras, the lens is also an important factor to determine the imaging quality. First of all, look at the zoom ratio, which refers to optical zoom. The greater the optical zoom ratio, the greater the degree to which we can choose the scene size, which will bring great convenience to our composition when shooting, which is the same as the zoom lens of a camera. Second, it depends on the aperture of the lens. If the aperture is small, no matter how large the pixel is, it can't shoot the dark light well. Needless to say, there is only one principle-the bigger the better.

2. What zoom is suitable for you? At present, digital camera products generally use 10 times the large optical zoom lens, and some products even reach 33 times. The large zoom lens will not have much influence on the imaging quality when shooting, and it will be very convenient when shooting large scenes. Here, we have to consider our own needs and choose where to shoot with DV. For travelers who like to travel around, it is very suitable to choose products with large zoom. If it is an ordinary user, then 10 times the optical change model is enough. There is no need to spend so much money on things you don't need at all. The LCD screen of digital camera is getting bigger and bigger, which has developed from 2.0 inches to 3.5 inches. Large-size LCD models are very popular in the market, suitable for friends with poor eyesight. However, the large LCD screen really has many advantages and few disadvantages.

In fact, the LCD screen looks comfortable, but it has at least two shortcomings. First of all, it increases the cost and makes it expensive. Generally speaking, the 3.5-inch screen model is more expensive than the 2.5-inch screen model with the same configuration in 500 yuan. Second, the LCD screen consumes a lot of electricity, which shortens the use time and has a great influence on outdoor shooting. Therefore, it is meaningless to pursue the size of LCD unilaterally. After all, we finally appreciate the filmed works on TV, so the LCD screen of DV should be practical! 2.5 inches and 2.7 inches are popular now. 1. Traditional tape DV. The main advantages of ordinary DV tape are its wide popularity and many users, and it can be used with various DV format machines. Easy to use, relatively low price, relatively stable and mature technology, and relatively cheap storage mechanism maintenance. From low-end entry to high-end machines, both brands, models and prices are very rich, which can meet the needs of all kinds of consumers. The main deficiency still comes from the later collection and compression editing.

2.DVD camera. Compared with traditional tape DV, DVD camera has the following advantages: First, DVD disc is smaller than video tape, so the machine is lighter and easier to carry. Second, it is more durable. Video recording requires constant contact between the video tape and the magnetic head. In DVD system, the optical laser head does not touch the optical disc, so it is less worn when recording and playing. Third, it can be read at will, DVD discs do not need to be rewound, and the search process can be basically completed in an instant. Fourth, the recording cannot be accidentally erased. When the video tape is placed in a video recorder or exposed to a strong magnetic field, it is easy to be erased. DVD can avoid this danger. Fifth, you can use DVD player to play the discs shot by DVD camera at any time.

The main disadvantages of DVD camera are: first, the life of laser head. Generally speaking, although the laser head does not touch the DVD disc, the temperature is very high. At high temperature, the life of laser head will be shortened, especially when shooting continuously, the body of DVD camera is very hot, and the temperature is obviously higher than that of ordinary DV. Generally, the body temperature of ordinary DV comes from LCD screen, while that of DVD camera comes from the high temperature emitted by LCD screen and laser head, especially in summer.

3. hard disk DV. Hard disk camera is naturally an important direction of DV development in the future. Compared with traditional DV, hard disk camera is much simpler than tape camera! There is no control circuit with bin, and the most important thing is the lack of drum assembly. So its failure rate will be much lower.

Compared with DVD cameras, the failure rate of hard disk cameras will be lower, at least there is no laser head with huge heat. Although the calorific value of hard disk DV is not small, as long as there is no problem with heat dissipation, it is not a big problem for hard disk DV to shoot continuously for a long time. Similar to DVD camera, the post-production of hard disk DV becomes easier, especially the acquisition and compression, because the compression has been completed at the time of shooting, and the acquisition is also completed through USB cable transmission. Compared with traditional DV, this is also quite convenient.

Of course, hard disk DV also has some shortcomings, mainly the capacity problem. At present, there are 30G, 60G hard disk DV and 30g hard disk on the market, and the standard TV broadcast mode can shoot about 14 hours. If the shooting content is not large, it is still enough. If you need to go out for a long time to shoot, I am afraid that the inability to replace the storage medium will be a big disadvantage of hard disk DV.

4. memory card DV. Compared with DV tapes, DVD discs and hard disks, memory cards have the advantages of small size, portability and easy replacement. The biggest disadvantage is that the capacity is too small and the price is relatively high. This is also an important reason why although the memory card products are mature, they cannot be widely used in cameras. Even a standard SD card with a capacity of 2GB can only shoot a high-quality maximum size of 15 minutes. Of course, if it doesn't take a long time in continuous shooting, it's good to prepare several large-capacity SD cards, which are small in size and light in weight, but the price of large-capacity SD cards is still not low at present. Imagine that it is unacceptable to prepare four 2GB SD cards in just one hour of shooting.