Otherwise, the file produced will be Enormous. Specifying a higher resolution will increase the amount of detail in the image and, correspondingly, create a larger file. The amount of resolution you need will depend on your application. If you are still confused about resolution, see Question 3 below on what to do if you do scan your image in at the wrong size for your needs. For a simple answer, though, the following rules of thumb should generally produce reasonable results.
Image files can be very large.
Use the minimum resolution that meets your needs. The number of different colors available to your image, referred to as color precision or color depth, will also affect the file size. Other options are 8 bits per pixel and 1 bit per pixel. The 8 bit per pixel option is particularly useful for grayscale images, while the 1 bit option is adequate for black and white drawings. 8 bit and 1 bit precision will reduce the size of your file by factors of 3 and 24 respectively.