CHAPTER 3
ELECTRONIC IMAGING
With the evolution of electronic imaging, the
technology involved today in the creation,
manipulation, and distribution of images allows
photographers to perform functions that they only
dreamed of a decade ago. Procedures that once took
hours or even days in the conventional darkroom can
now be accomplished within minutes under normal
room lights and without getting your hands wet. With
the electronic medium, images may be created,
modified, and enhanced, The end product is limited
only by your imagination. Several distinct advantages
of electronic imaging as compared to conventional
photography are in use today. These advantages are as
follows:
It saves the time required in conventional
development and printing.
It saves money by eliminating direct and
indirect costs related to developing and
printing photographs.
It is environmentally friendly.
It can be viewed immediately.
Images can be transmitted instantly and rapidly
using standard telephone lines.
Electronic imaging used in the Navy today ranges
from capturing and processing an image through an
electronic medium to conventional silver-halide
technology and electronic processing by way of a
hybrid system. Because of the dynamic advances in this
growing field, this chapter is intended only as a brief
overview of the basic principles and applications of
electronic imaging. To be prepared for this fascinating
technology, you must become familiar with computer
systems, electronic imaging, and the equipment used to
create digital images.
BASIC COMPUTER FUNDAMENTALS
Computers are often compared to people since both
have the ability to accept information, work with it,
store it, retrieve it, and provide information output. The
primary difference is that people have the ability to
perform all of these actions independently without
outside assistance. People also think and control their
own actions. The computer, however, requires a
program (a predefmed set of instructions) to accomplish
an assigned task. People receive information in several
different forms, such as eyes, ears, nose, mouth, and
even sensory nerves. Our brain receives and accepts
this information, works with it in some manner, and then
stores it somewhere in the back of our mind (memory)
for future use. If information at the time requires
immediate attention, our mind directs us to respond
with words or actions. Likewise, the brain of a
computer is the central processing unit (CPU). The
CPU is designed to do basically the same thing; that is,
it receives information (input data), works with this
information (processes data), and transmits this
information (output data) to some form of output media.
Computers are incapable of independent thought or
action; they can do nothing more than perform the
instructions given to them. Computers simply follow a
set of instructions stored internally (called a program)
and process the input data. Then when all the steps are
followed properly, the computer provides an end result
that you can work with.
The computers used in electronic imaging are
general-purpose digital computers. These
general-purpose computers are capable of performing
operations, such as word processing, graphic
applications, and spread sheet because they can store a
wide variety of programs in internal storage.
COMPONENTS OF A DIGITAL
COMPUTER
Components, or tools, of a computer system are
grouped into two categories: HARDWARE and
SOFTWARE. Hardware consists of the machines that
comprise a computer system, such as all the mechanical,
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