However, scanning still involves more than pushing a button. Scanners capture images by shining light onto the document being scanned. Since dark areas reflect less light and light areas reflect more light, the CCD can convert the light into digital information called bits for binary digits. The final image is then a reconstruction of this data by the scanning software. The greater the dpi number, the higher the resolution and resulting file size.
Resolution is where most people make mistakes when scanning.
Everybody likes to see a Web page with many eye-catching graphics but nobody wants to wait until they all load, especially if using a modem for Internet access. Therefore, it is extremely important to be scanning at the proper resolution. The proper dpi settings will result in the best looking graphics at the smallest possible file size. Scanning at higher dpi settings requires more time, more computer memory, and more disk space. Therefore, if you do not plan to resize your image, scan at 72 dpi.