Resolution Resolution determines the level of detail recorded by the scanner. The greater the dpi number, the higher the resolution. Remember, the resolution of the image and also the resolution of the output device determine the quality of the image. A high image resolution can simply make file sizes unmanageable or waste disk space without yielding any visible improvement to the image. When dealing with resolution, you should distinguish between optical and interpolated resolution.
Interpolated resolution is resolution enhanced through software.
Choosing the best resolution setting Scanning at a higher resolution requires more time, memory, and disk space than at a lower resolution. When choosing a resolution setting, consider the type of output for which the image is scanned. A higher-resolution image will not be any clearer on the monitor and will simply create larger files and larger images on the monitor. Remember that the higher the resolution, the larger your image file size , select the lowest possible resolution that still provides good image quality in order to keep file sizes manageable. When to use high resolution High resolution is important for processing an image through a high-end color system or for enlarging an image.