Comparing Traditional Photography and Digital Imaging
The traditional photographic process that has defined image reproduction for over 150 years involves a long drawn out series of chemical reactions beginning with the capture of light on silver film and ending with the fixing of the image onto paper or a transparency through the development processing. The final image is analog, which means it is composed of continuous gradients that are analogous to the gradients seen in the world around us.
Digital imaging, however, requires a completely different process. The image must be captured electronically on a light sensitive silicon chip. Each silicon chip contains thousands of pixels, which is "picture" plus "element", which measure light, color, and contrast. Because each pixel is a square and uniform in dimension, each individual one can be changes by means of a computer. The size of each pixel is determined by the resolution, which is the number of pixels per square inch. The key difference between an image on film and a digital image is the resolution. For example, when you look at a painting, you see many separate pixels that form the whole painting to form a conceptual process. When thousands of pixels are formed together in a digital image, you form one single image that leads you to view the photograph as a single view. In 1995 Kodachrome film had a resolution equivalent to 18 million pixels, the best digital camera had a resolution less than one tenth of this. As this capability continues to grow and improve, however, other means of digitizing photographs have become the medium choice for altering images. If an image is analog to begin with, it must me converted to a digital form, hence turning it into a series of 0’s and 1’s that a computer can read. A scanning device does this, before the image can be read on screen. When turning an analog image into a digital image, it changes the process of development from chemical to mathematical, because each pixel is represented my a number and stored in the computers memory for easy reading. This process makes the image true and impossible to tell how many duplicates of the image have been made.
Once information is in its digital form, it becomes very simple to save, alter, and duplicate. Because each pixel can be enlarged and changed on the computer screen, each piece of the image can be altered at will. Elements can be added or subtracted, changed in color, brightness, or contrast. Areas of the picture can be copied and moved to other areas of the image where other things have been removed, and this can be repeated indefinitely. People can be made fatter or thinner, the color of hair and eyes can be changes, or completely removed from a picture is so desired. When the image is finished, it can be printed or sent via telephone lines or satellite anywhere in the world.
Traditional photographs may be altered in four basic ways: in the set up of the model, camera,...