1. The color mode is adopted during scanning, so as to be as faithful to the original as possible, improve the accuracy, and provide conditions for smoothly removing the back graphics and texts that penetrate the front of the paper.Improvement Of Scanning Quality Of Black-And-White Printing

2. Using Photoshop software to convert the scanned image into gray image can effectively solve the problem of paper yellowing. Improvement Of Scanning Quality Of Black-And-White Printing

      The author found that this is better than directly using the scanner to scan in gray mode.Improvement Of Scanning Quality Of Black-And-White Printing

3. Remove the back image and text penetrating into the front of the paper. Improvement Of Scanning Quality Of Black-And-White Printing

    The theoretical basis is that even if the text printed on the back of the paper penetrates into the front of the paper, it is still obviously different from the text printed on the front. Improvement Of Scanning Quality Of Black-And-White Printing

     In other words, the gray value of the front picture and text is lower (i.e. darker), while the gray value of the back picture and text seen through the front is higher (i.e. whiter). Improvement Of Scanning Quality Of Black-And-White Printing

     We can filter out the parts with higher gray value by adjusting the color level (using the image \ adjust \ levels menu command), so as to remove the annoying back graphics and text. Note: Improvement Of Scanning Quality Of Black-And-White Printing

      do not use the auto levels command to automatically adjust the color scale, otherwise the effect is very poor.Improvement Of Scanning Quality Of Black-And-White Printing

4. color adjustment: just adjust the ends of the input Input Levels in the dialog box, and you will achieve very good results.Improvement Of Scanning Quality Of Black-And-White Printing

▲ move the input color scale white slider (triangle on the right) to the left with the mouse or directly enter the value in the text box on the right to filter out the parts with higher gray value (here is the picture and text on the back).Improvement Of Scanning Quality Of Black-And-White Printing

▲ move the input color scale black slider (triangle on the left) to the right with the mouse or directly enter the value in the text box on the left, so as to darken the part with low gray value (here is the front picture and text).Improvement Of Scanning Quality Of Black-And-White Printing