This section examines the basics of modern digital image capture, and how various technologies come together to create digital images. The photographic process works much like the human eye. The eye has a lens that collects light that passes through an adjustable iris and strikes the retina. There it is translated into electrical signals that travel through the optic nerve to the brain for processing into the images we experience. The modern digital camera replicates this process – it has a lens, and an adjustable iris through which the light is collected onto a light sensitive surface.

This video lesson goes through the process whereby light falling on the light sensitive surface is translated into electrical signals that represent the differing brightness values of red, green, and blue colors—which are then assembled, via interpolation through a de-mosaicing algorithm, to produce a full color image. The nature of the "pixels" is explored, and resolution is defined relative to output size. Finally, the common image file types are examined and the practical uses of the different types revealed.