I know nothing about digital cameras. Please introduce a video tutorial that can teach me digital camera knowledge and buying skills.

Medical Introduction: What is a digital camera? Basic structure of digital camera.

For beginners of DC users, we must first have a basic understanding of these two issues. 1. What is a digital camera and what are its advantages compared with traditional cameras? 2. What are the basic components of a digital camera? As the beginning of this article, the author will start this article with this problem as the starting point.

The most basic understanding of digital cameras is that they don't need film and have LCD screens. With this function, traditional cameras and digital cameras can be quickly distinguished (not excluding a few exceptions). From the internal structure, a large number of electronic components are used in digital cameras, and the design is more complicated. The medium used for photosensitive has also changed from film to photoelectric device. This difference makes digital cameras have many advantages.

First of all, digital cameras can take photos as they are built, and they can also take accurate photos through LCD screens. At the same time, due to the different storage media, digital cameras save a lot of film costs. According to a survey, 90% of the photos taken by most users are preserved, and they are not deliberately developed into photos. In other words, most of the works we shoot are only stored in computers for browsing. This means that we can save a lot of printing costs and time. Thirdly, the photos of digital cameras can be easily edited with various image software on the computer to achieve various effects. Of course, nothing is perfect, and digital cameras also have many unsatisfactory places.

A digital camera consists of lens, photoelectric conversion device (COMS/CCD), analog-to-digital converter (A/D), microprocessor (MPU), built-in memory, LCD, mobile storage, interface (computer/TV interface) and lithium battery.

For the composition of digital cameras, photoelectric converters, analog-to-digital converters, microprocessors and internal and external storage systems are all unfamiliar. In fact, photoelectric converter is also the "negative" of digital camera, but it can be reused, while the negative of traditional camera can only be used once. A/D converter sounds very complicated, but it is actually only a device for signal conversion by photoelectric converter. It functions like a radio, converting radio signals into sounds that we can hear. Microprocessor is the heart of digital camera. It converts the signal of digital-to-analog converter into a specific image format after re-processing. The internal and external memory system is the "film barrel" of a digital camera, and the photos taken are stored here.

By now, you should have a comprehensive initial impression of digital cameras, so the following related introductory knowledge will further strengthen your understanding of digital cameras.

Main medicinal materials (four supplements): four elements that must be understood to understand digital cameras

As soon as we came into contact with the world of digital cameras, a bunch of new words swarmed in. Resolution, pixels, digital zoom, interpolation, etc. At first glance, getting started is difficult; What I want to do here is to polish this boring noun. Describe it to everyone in the form of spoken and vernacular. If you are new to digital cameras, the following questions are particularly important. But this does not mean that other details can be omitted. After all, catching the thief first catches the king, and the emphasis is different.

1. Resolution and pixels

When we come across digital cameras, we often see such parameters as "2304X 1728, 1600X 1200,1027x768,640x480", which is also commonly known as the resolution. So what do they mean? I believe that mosaics are well-known building materials, so these parameters are like the number of horizontal mosaics multiplied by the number of vertical mosaics, and each mosaic represents a pixel. A picture is made up of these colorful mosaics. Enlarge the part of the lotus in the picture below by 1600 times, and we can clearly see that the color blocks of the mosaic are actually the corresponding pixels.

The highest shooting resolution of a camera is generally similar to its pixels. Take 2304X 1728 given above as an example, then the maximum effective image number of this camera is 2304 *1728 = 3981312, and the approximate value is 4 million. In other words, this is a 4 megapixel digital camera. Similarly, we can also calculate the pixels corresponding to other camera resolutions. The author gives the corresponding reference table here. Of course, the camera settings are different, which may be different. Generally, as long as you choose a camera from a specific manufacturer, the given resolution is fixed, and users can switch between different resolutions but can't customize the resolution.

2. Resolution and printing

Usually our photos are developed through film, while digital cameras have no film as a medium. We can watch the photos clearly and intuitively and develop them. So, what does resolution have to do with printing? For you who are new to digital cameras, there may be a lot of confusion about printing. There may be some unnecessary jokes, so the author will talk about the relationship between them in detail.

First of all, it is obvious that the higher the resolution, the larger the printed picture and the better the quality. Of course, this is not without conversion rules, and there is a corresponding relationship between them. Referring to similar materials, I found that the explanation of this kind of problem is still too simple and professional, and I often see it in a fog. In fact, digital printing is closely related to the printing equipment used by printing plants. This paper introduces a unit DPI, which is used to describe the printing resolution of the printer. Generally speaking, the resolution of a digital printer is 300DPI. What does this mean? In other words, there are 300 ink dots per inch on photographic paper. It can also be understood that one ink dot corresponds to one pixel. In this way, we can accurately calculate how big the digital photos we take can be printed.

For example, the optimal size of 1600X 1200 digital photos output by a 300DPI printing device is 1600/300=5.3 inches, and 1200/300=4 inches, that is, 5.3×4 inches. In actual processing, this size is generally enlarged by a digital printing shop, and finally cut into 6×4 inch photos, commonly known as 4R. Of course, after this adjustment, the picture quality is slightly reduced. On the other hand, we can get the actual image printing resolution of 1600/6=267DIP. Of course, this decline is not obvious to the naked eye and can be ignored. Of course, by reducing the printing resolution, we can enlarge our photos by 1600X 1200, with a maximum magnification of 7 X 5 inches, which is 5R.

Finally, we can get the formula. If the resolution of the digital printer is N DPI and the resolution of the photo is Y X Z, then the photo we can print is a photo with a length of Y/N and a width of z/n..

3. Interpolation and pixels

The term interpolation is also unique to digital devices. Although many friends who come into contact with digital cameras have heard of this term, they don't care. But this word once became a prop played by profiteers, and it did fool many people. Through one interpolation, the pixels of the digital camera are rising, so the interpolated pixels here are calculated according to the size of the final output picture. For example, the original CCD can only shoot a picture of 640X480, which is 300,000 pixels. Through software amplification and interpolation, the output picture becomes 1024X768, which is 800,000 pixels. Then let's say that the interpolation pixel of this camera is 800 thousand, and the actual pixel is only 300 thousand! The effective pixel of the digital camera FinePix F4 10 given above is 365,438+million, which is 6.03 million after interpolation.

If a digital camera writes 5 million interpolated pixels on the leaflet, it actually means that the camera has no pixels at all. Interpolation is the process of calculating the adjacent pixels of the image through the software part inside the digital camera to get a new pixel, thus improving the resolution. To put it bluntly, the image is not that big, but it is enlarged by software. This process is very easy to simulate in computer image processing. Although interpolation improves the resolution, it is the result of software operation after all, which is different from the real color and will produce jagged edge and blurred edges.

4. Optical zoom and digital zoom

There are essential differences between digital zoom and optical zoom, but some businesses just confuse them. Therefore, for beginners, it is more important to clearly distinguish the difference between the two.

Optical zoom is a real zoom, which depends entirely on the physical structure of the optical lens. To be clear, the movement of the front lens of a digital camera that we usually see is optical zoom. However, in the design concept of digital cameras, some models pursue compactness and exquisiteness, and naturally give up the optical zoom lens like a cannon. In order to make up for this deficiency, designers use software to realize digital zoom. Digital zoom is actually a process of enlarging a part of the original image to the whole picture. In this process, the interpolation operation of digital camera is passed. So this visual closeness doesn't make much sense.