Prospect of the hottest digital photography techno

Prospects for the application of digital photography in printing

the content of image form is an important reproduction target in printing media. Most of the images recorded by silver salt materials in the past have to be converted from scanning to digital file form, and then integrated into a part of printed matter by typesetting operation. Recently, the technology of digital photography is becoming more and more mature, and the way of directly shooting electronic image originals is gradually popular. The basic principle, operating characteristics, equipment status, application practice and future direction are briefly introduced in this paper

basic principle

the process of digital image is not strange in the environment of digital printing, because Adobe Photoshop like image processing software has almost become one of the standards of prepress operation, but there are some similarities and differences in the basic concept of using a scanner to obtain images or using a digital camera to obtain images, which need to be explained in advance

digital cameras, like scanners, project images onto photoelectric sensing components through the focus of optical lenses to form image pixel units. However, the light source of the scanner is fixed, and the scanned object is roughly in the form of a plane; The object taken by the digital camera can be in the form of three-dimensional, and the intensity and color temperature characteristics of the on-site light source can change. It is relatively complex, so we should pay special attention to it in use

compared from the production process, when using film to record images to print, there will be varying degrees of signal loss in the three stages of film exposure, chemical development and substrate scanning; However, the digital camera directly captures and generates electronic files, and the process is only once lost! Therefore, in terms of the distortion rate of the signal, direct photography by digital camera can have better image quality, and at the same time, it can shoot and see immediately to improve the timeliness

however, the image quality obtained by digital cameras today may not be better than that obtained by negative scanning. There are many reasons, such as lens optical quality, CCD quality, software ability or cost-effectiveness, etc., but from the perspective of principle, it has considerable room for improvement and great potential

operating characteristics

generally, when operating the scanner, the size between the original and the copy, that is, the finished product with greater material stiffness, will be used as the calculation benchmark of magnification, so it is not necessary to distinguish the difference between pixel and dot, but pay special attention to this relationship when taking photos with a digital camera

pixel is generally the analysis unit when the input device samples the image light source. For example, the overall sampling capacity of the digital camera is based on the pixel. The particle is each imaging entity unit that can be controlled by the hardware equipment. For example, the printer takes the control ability of how many ink dots are in the unit inch as the unit of measurement (DPI) of its resolution, and the laser film output machine also takes how many DPI can simulate how many print lines as the specification

in use, the general principle is to deduce the size that can be presented by the input image file from the resolution of the output device. For example, for 150 line printed matter, the resolution of 300dpi will be used to divide the pixel amount of the digital camera and calculate its printable size. If 6million pixels (3000 × 2000), you can print out 10 × 6.6 inch image size. The conversion principle is defined by the relative size of the fixed file under different resolutions, that is, the principle of the data conservation law proposed by the author. In practice, it still involves the characteristics of image quality coefficient and so on, which is more complex. Interested readers can read my book "digital photography technology" in detail, or please refer to the reference station

current situation of equipment

the speed of digital camera innovation is amazing, and the price adjustment also attracts eager photography lovers

, but there are several phenomena that should be paid special attention to. It is generally believed that the higher the pixel is, the better the image quality is. In fact, it is not, because the resolution is divided into optical resolution and electronic resolution. The latter is obtained from the former through mathematical calculation, which is a virtual number. Under the same optical resolution, the quality of the actual image is the real focus, which involves the quality of the lens, the amount of photoreceptor noise and software processing ability. It is quite complex, but the best way is to take actual photos to compare

the current digital cameras are roughly divided into three levels, ranging from tens of thousands of yuan, hundreds of thousands of yuan to nearly one million. In the range of tens of thousands of yuan, common digital cameras for dummies are more than enough to take daily photos or pages affected by the APEC meeting. Recently, the interchangeable lens digital camera developed by the old monocular camera system is the favorite of professional photographers, because the old lens and other equipment are compatible with its system, and the mobility and rich control functions of monocular cameras are almost the same as using the original advanced monocular camera. The only disadvantage is that there is still the problem of lens magnification, which is very painful to shoot at a wide angle, but the improved model will soon be on the market! The system equipped with a large camera and a digital back is a powerful tool for commercial photography. Because of its large file, it can also control the perspective angle such as the tensile strength of the expanded polystyrene board perpendicular to the board surface, but the price is nearly one million, and the economic threshold is high

application practice

it has been 20 years since the first generation of digital cameras. The shadow of digital cameras can also be seen everywhere on the streets. There are also professional applications in mail order catalogue and wedding photography in China. Almost every person has a digital camera, but does it mean that the image quality is improved at the same time

in the past printing process, the physical photos and slides in the standard environment can be used as the basis for photographers to layout and communicate with prepress operators. However, in the process of digital photography, only the actual image files are used as the originals for communication and production, but each computer screen has its color characteristics, so the images presented will fall, Therefore, digital proofing or color management system has become an important cooperation project. At the same time, photographers in the past only operated cameras, but now they also need to operate computer equipment. These additional technical costs and capacity requirements are not very explicit factors, which should be paid special attention to in application

future prospects

the timeliness and convenience of digital photography are its irreplaceable advantages, but at this stage, its image quality and economic benefits are still rapidly improving the reasons for this kind of phenomenon. With the large investment of Taiwan's electronic industry, new digital cameras will become as popular as scanners. For the printing industry, the image produced by digital photography has not