Electronic cameras use one of three devices to store images. These three devices are a 2-inch video floppy disk, a hard drive or Random-Access Memory (RAM), and an integrated circuit (IC) card or chip. In  the  198Os,  the  still-video  camera  was  introduced in the Navy. The still-video camera uses a 2-inch video floppy disk capable of recording 50 or 25 images. The number of images that can be recorded on a floppy disk depends on whether the image is recorded in the field" or "frame" mode. The FlELD MODE uses one track per image on the floppy disk and allows 50 images to be recorded on one disk.  The  field  mode  provides  poorer  resolution because there are less pixels per picture. The FRAME MODE uses two tracks per image and allows 25 images to be stored on one floppy disk. The frame mode provides higher quality because more pixels per image are  recorded. Still-video cameras use an analog signal to record the images. This variable waveform represents density and colors that are created electronically by the intensity and the color of light striking an image sensor within the camera. This analog signal is the same type of signal used to record most motion-video images. It is also the same type of signal used in conventional television. Many still-video cameras have a playback capability and may be connected directly to a television monitor to view the images. An analog signal records the lowest resolution of the electronic cameras, thus using the least amount of memory per image. Most still-video cameras have a limited resolution of approximately 380,000 pixels. A still-video camera used by the Navy is the Sony Pro Mavica MVC-5000. This camera has three CCD chips that are used as the image pickup device and the high-band format to improve resolution. An important factor to remember is that a still-video camera is an analog system, not a digital system. The format and configuration of a still-video floppy disk is different than that of a computer system, which is digital.  By  using  the  appropriate  hardware  and software,  you  must  convert  an  image  captured  on  a still-video camera from analog to digital format before it can be modified or printed in a digital-imaging system. Still-Digital  Cameras A  still-digital  camera  is  superior  to  a  still-video camera. As the name implies, a still-digital camera records an image in digital format. This digital format uses the binary system of "0s and 1s." The combination of these digits represents densities and colors created electronically  by  the  intensity  and  the  color  of  light striking an image sensor within the camera. A digital image has a much higher resolution than an analog image. This higher resolution provides more pixels per image, but it also requires much more memory per image. Digital cameras use an IC card or chip and RAM or a hard drive. The RAM is built permanently into the camera and must be downloaded to  another  storage  device.  This  storage  device  is  an internal or external hard drive. This hard drive is similar to  the  hard  drive  found  in  personal  computers.  Kodak’s Digital Camera System (DCS) uses a hard drive to store images. The Kodak DCS still-digital camera combines a Nikon F-3 body and a standard lens with a digital-image back   to   capture   high-resolution   color   or black-and-white images. The Nikon body operates similar to a camera with conventional film. The major difference  between  the  Nikon  being  used  with  film compared to the DCS back is that the image area of the DCS is only one half of the size of a 35mm-film frame. This change in image area affects the effective focal length.  For  example,  a  conventional  35mm  lens becomes a 70mm lens with the DCS. The Nikon F-3 functions, aperture settings, shutter speeds, and light metering operate the same as with film. Three major components that make up the Kodak DCS are as follows: an electronic back, a camera winder, and a digital  storage  unit. Kodak’s DCS models have a digital-image back that contains a 1,280 by 1,024 pixel CCD imager. This means the CCD is capable of recording about 1.3 million pixels. The color back equates to film speeds of 200,400, and 800. The monochrome back equates to film speeds of 400, 800, 1600, and 3200. With a winder (spooler), you can shoot up to 2.5 images  per  second.  The  system  has  a  standard  6 megabyte (Mb) buffer that can store six images in one burst.  Thus it is possible to shoot faster than the images are  stored. The camera body of the DCS 100 is tethered to a Digital Storage Unit (DSU) that contains a hard drive. The  200Mb  hard  drive  can  store  158  uncompressed images or about 600 compressed images. The DSU also has  a  key  pad  for  system  control  and  a  4-inch monochrome monitor so you can view the images immediately. 3-9