What is the appropriate resolution for scanning images?
That really depends on what you’re going to do with the image. An image for a web site needs to be 72 dpi; however, you may want to scan at a higher resolution if you need to do image retouching, and then scale it to 72 dpi when you’re finished. If the image is for an on-screen PowerPoint presentation, then 100 dpi is best. While a higher resolution file can be used in PowerPoint, it will slow down the on-screen display and you won’t see any improvement in image quality. If you plan on having a photographic quality slide or print made, then you will need 300 dpi, perhaps more depending on the resolution of the output device.
