2. Background

2.1. Digital Camera Technology--How Things Work

Digital cameras work with the same basic concept as a traditional camera. They have a viewfinder or LCD screen to show the image prior to taking a photograph, a lens with a shutter behind it to allow the light from the subject to hit a light sensitive material. However, this is where most of the similarities end.

Digital cameras use a CCD (Charged Coupled Device) to sense the colors of the light and their intensity. The CCD can be likened to a very find piece of graphing paper, with thousands of little squares (transistors) to which sense the differences between the colors. There are three types of transistors used in commonplace CCDs, red, green and blue. Each transistor then passes the color and intensity it sensed to and Analog-to-digital converter (ADC). The ADC then converts the information passed to it by the transistors into a digital format, or binary 1's and 0's. The digital output of the ADC is then passed to a Digital Signal Processor (DSP). The DSP adjusts the contrast and other image details to get the perfect look and then compresses the data into a file format like JPEG (Joint Photographics Expert Group).

Digital cameras may also have the ability to do an optical or a digital zoom on an image. An optical zoom is when a lens is used to get a closer look at the subject. A digital zoom is used to enhance the optical zoom for a larger image even though the maximum size has been attained via optical zoom. Even though an image can be resized later, it is suggested to use the built in digital zoom of the camera at this point before any compression has been done to the image. File formats like JPEG tend to degrade in quality when resized more so then when the image is resized by the camera's software. This is due to artifacts left behind from the compression.

A good resource for definitions of the terms used above is http://photo.askey.net/articles/glossary/ Please refer there for more information. Kodak also has a good site with much information on how things work, http://www.kodak.com/US/en/digital/dlc/.

2.2. Kodak Digital Camera Product Line

The technical specifications for the cameras in the Kodak Digital Camera product line have been attained from owners of the cameras and from third party web sites. None of the information in this section has been taken or compared to any Kodak documentation or their web site. Please submit missing and or incorrect information not obtained from copyrighted Kodak materials to khemicals@marblehorse.org. This information is useful to not only track the progression of digital cameras and as a comparison tool but also for many other technical uses.

2.3. Communicating With Digital Cameras