Conventional analog imaging systems have been used for many
years for capturing and processing images for the print industry. Digital imaging
has had a significant impact in print and Web workflows, as the electronic preparation,
capture, manipulation, and processing of images easily occurs at the desktop.
Analog images are created from a photographic process
that uses film in a camera as a means to capture the image. The image
is called a continuous tone image, consisting of a range of smoothly
graduated tones. There can be thousands of tonal values that are present
in continuous tone images, regardless of whether it is a black and
white or a full color image.
Digital images are created by filmless processes,
which record the image on media such as internal computer memory,
a CD, a floppy disk, or flash memory. Digital cameras and scanners
are the devices used to capture the image which then is processed
and displayed in graduated tones constructed of thousands of individual
cells or pixels, often presented in a square shape. Instead of being
a continuous tone of colors, the cells form a grid of color elements
placed together in rows and columns. As the image is captured, the
color data is recorded in bits or bit depth. Bit depth forms the resolution
of the image. As the amount of data (bits or bit depth) increases
by using devices that are capable of recording more data, the amount
of colors that can be reproduced increases. A higher resolution will
provide a greater amount of colors, and therefore, a smoother gradation
of color tones.
The various stages of image development are being effectively
integrated into enterprise publishing systems to allow greater efficiency and
increased functionality for all aspects of layout, design, and output. At the
beginning stages of the process, there are several devices that are utilized
to capture images:
- Process Camera - a device that uses film to capture analog images.
- Digital Camera - a filmless device used to digitally photograph and capture
images as an electronic file.
- Scanners - a device to digitize the light and dark color values of flat
art, slides, or photographic prints and convert the values into an electronic
- Kodak's Photo CD's - a device to capture images that exist on film and
are then stored as an electronic file.
Note: When planning for digital image capture, with either
the scanner or the digital camera, remember to consider the resolution
bit depth best suited for your needs from capture through
output. The image resolution will be measured in dots per inch (dpi)
and the bit depth will be measured in bits of color recorded for each
pixel. The higher the dpi, the better the resolution. The greater
the bit depth, the more colors that are represented, providing a better
reproduction of the captured image.