What are the advantages and disadvantages of digital photography?

Advantages and Disadvantages of Digital Photography

Digital photography is in line with the trend of the information age, and has many advantages over traditional chemical film, such as instantaneous, editable images, reproducible with full fidelity, and easy to retrieve and transmit, and so on. Immediate capture is obvious, press the shutter, you can see the effect immediately, unlike traditional film that has to wait until the development or even after printing and releasing. The editing of images has also become widely known with the popularity of "computerized portraits", which allow you to change the background, clothing, hairstyle and even fix flaws after the photo is taken. A digital photo is a data file, very easy to retrieve, snap your fingers and you can copy any time without distortion or sent through the computer network to any corner of the world, which I'm afraid is the most difficult to reach the traditional photography, with the people's concept of updating, "photo" does not necessarily have to be printed on paper, electronic albums are gradually accepted by the public, the advantages of these advantages will be even more obvious. This article is not about these obvious advantages, but the deeper level, that is, the digital photography art in the expression of the advantages and limitations, in other words, digital photography is best at showing what kind of theme, in what aspects of the most unsuitable.

The tool of digital photography is the digital camera, and the heart of the digital camera is the imaging chip, which, today, is the color CCD. The only difference between digital photography and traditional photography is that traditional photography records image signals on film, whereas digital photography records image signals as data files through CCDs. CCD is a device to quantify the image information, using a series of data to describe an image of the details of the color and brightness and other information. Comparatively speaking, traditional chemical imaging is a simulated record of the subject, the color record is not only related to the shooting process, but also depends on the performance of the film itself, as well as the process of expansion, the expansion of the temperature changes or changes in the performance of the solution, may make the final result is not the same. The recording of color in digital photography is quantitative, with the color of a given pixel point being a definite value that is very close to what is displayed or output every time, as long as the display or output device is tuned to a standard. For images that are rich in color but have smooth transitions, image processing software can calculate the transitions as close to reality as possible, thus interpolating and enlarging them without distortion. Therefore, the advantage of digital photography lies in its perfect color reproduction, which makes it ideal for representing objects that have continuous colors rather than lines or dots, such as close-ups of people's faces and still lifes.

There are advantages and limitations, the so-called limitations, of course, is compared with the traditional chemical imaging - film - before exploring the limitations of digital photography, we may wish to first understand the chemical imaging. Chemical imaging imaging unit is the molecular level, carefully designed to image the shape of the chemical particles, after perfect control of the parameters of the process, you can record almost any image that the lens can distinguish. In the performance of color images, the film uses a three-dimensional layering method, the profile of the ordinary negative film as shown in the figure below, the reversal film is similar, except that the performance of each layer is different. In imaging, each emulsion layer only reacts to one of the three primary colors, generating its complementary dyes, so the separation of the complex colors that make up a point is overlapping, and will not reduce the image resolution and sharpness due to color separation.

In contrast, the CCD imaging unit of a digital camera is an electronic component with a certain physical volume that cannot be made as small as a molecule, which makes the resolution of digital photography somewhat limited. Moreover, in the formation of color images, the CCD adopts a planar segmentation method, the more common G-R-G-B type CCD structure is shown below on the left, light-sensitive when each light-sensitive unit to record the color value of a primary color, in the signal processing, by a-b-g-h four-point calculation of an RGB value, as a pixel recorded, at the same time, b-c-h-i, g-h-m-n, h- i-n-o are each calculated as a pixel, which can be simply understood as a "pixel point" formed by the center points of the four photoreceptors. Although this method cleverly solves the problem of recording color signals, the shortcomings are also very obvious. First of all, because the color value of each pixel is calculated by several neighboring photoreceptors (note that Worried Sky used the concepts of "pixel" and "photoreceptor" to show the difference), which inevitably reduces the resolution and sharpness of the image, and because the photoreceptor points that form a pixel are not physically located. And because the light-sensitive points forming a pixel are not physically co-located, there is a certain amount of displacement, which brings about errors. If the two adjacent areas of color, brightness, etc. is the same or continuous change can also be correctly restored, if the difference is very large, the calculation will produce a large error, the demarcation point do not know that should be attributed to that side, only to take an approximation, so digital photography is not suitable for the performance of the complex color points and interlacing lines.

Chemical film is only light-sensitive when shooting, and the developing process takes place in post-processing, so as long as the mechanical speed keeps up, high-speed continuous shooting is possible, while digital cameras have to process and record data after shooting, which takes a certain amount of time, especially when the shooting precision is high, the amount of data is very large, and it takes even longer. Although this problem can be alleviated by increasing the internal cache, it cannot be solved fundamentally, so it will be more inconvenient to capture with a digital camera.　As the factors affecting the chemical imaging process is very much, so that there is a certain degree of uncontrollable and unpredictable, which may produce a variety of unexpected artistic effects, greatly increasing the charm of photography, digital imaging standardization so that the imaging process can be controlled, predictable greatly improved, on the one hand, this is a major advantage, can be a faithful expression of the photographer's intentions, but in the artistic creation may have the possibility of become a major limitation, the process of the middle rule, greatly restricting people's creativity, and thus lose the artistic characteristics.

Digital photography is relatively inexpensive, and those who have the means can handle it themselves.