There are two factors that affect the quality and the file size of an image captured with a digital camera. The first is ‘file compression’. Compressing an image reduces the amount of memory that is taken up by the image and allows for more images to be stored on a memory card or disk. With modern digital cameras, an uncompressed image can take up to 10 Megabytes of data on the memory card. Since most digital cameras come with 8 -16 Megabyte cards, compression must be used to reduce the file size so that many images can be stored on a single memory card.
The trade-off for compressing an image is a loss of image quality. Using JPEG compression (the most common compression format) a compromise is struck between file size and image quality. The user of a digital camera has the option to change between different levels of compression to suit their needs. Compression can also be adjusted after the image is downloaded to a computer. However, it is not possible to uncompress an image. Once the image is compressed then there is no way of getting back to the original uncompressed image.
TIFF format is often employed by digital cameras for storing images without any loss of quality from compression. Images recorded in the TIFF format are of the highest quality but have a very large file. TIFF format is ideal for recording images that will be printed in large sizes.