In fact, check image brightness the easiest method is to compare with the original dead in CYMK mode, try to read out the scan image color values to see whether it is close to quadrochromatic.

• 实际上，检查图像亮度最简便的方法就是与原槁比较，在CYMK模式下试着读出扫描图像上的色彩值，看其是否接近原稿。