如何正确看待数码相机的高像素

一张照片所含的像素决定于数码相机的感光传感器CCD的像素数和打印机的解像率，而照片的清晰度又决定于照片上单位面积所含的像素数，后者等于该照片所含的总像素数除以照片的面积。因此，对于一般仅仅打印5×7英寸照片的业余照相爱好者、低端用户，宜选用200万像素的数码相机；对于需要打印最大达14英寸照片的照相爱好者、中端用户，则宜选用500万像素的数码相机；而对于制作供印刷厂16K满版照片用的专业人员，则应选用600—800万或更高像素的数码照相机。本文对此详细加以阐述。

How to Interpret the High Pixel Number of Digital Cameras

The total number of pixels enclosed in a the photo sensor CCD of the digital camera and the photo print depends upon the pixel number of resolving power of the printer, whereas the definition of a photo print depends upon the number of pixels enclosed in an unit area of the print, which in turn is equal to the total number of pixels enclosed in that print divided by the size of the print. Consequently, it is appropriate to choose a 2M pixels digital camera for a low-end amateur photographer commonly enjoying with 5×7 inch size photo prints, and a 5M pixels camera for a medium-end photographer interested in enlarging print to 14 inch size,whereas for a professional photographer making 16K full format pictures for a printing house, it is proper to choose a 6-8M pixels digital camera or so on, this paper elucidates in detail this problem.