Another storage medium is the video disk which is capable of storing large quantities of images. However, since these are analogue images, the quality is less good than digital pictures and analogue images deteriorate each time they are copied. There are three possibilities for image capture. Existing prints, slides and transparencies have to be transferred into digital media by means of a scanner. This is a process which is well established and for which there is no other alternative if the existing record system includes photographs.
Scanners come in a wide variety of capabilities and prices.
Three important criteria are color, resolution and speed, the latter of which is often overlooked. For instance, in the present selection of color flatbed scanners at 400 DPI resolution the range of time for one scan is 15 seconds to 12 minutes. Again, it is important to match the resolution of your scanner to the purpose of the images. Also remember that you should recalibrate your scanner for color matching quite frequently. It is quite possible to use an ordinary video camera with a special video board to get images into the computer.