Radiographic definition is the abruptness of change in going from one area of a given
radiographic density to another. Like contrast, definition also makes it easier to see
features of interest, such as defects, but in a totally different
way. In the image to the right, the upper radiograph has a high
level of definition and the lower radiograph has a lower level of
definition. In the high definition radiograph it can be seen that
a change in the thickness of the stepwedge translates to an
abrupt change in radiographic density. It can be seen that the
details, particularly the small dot, are much easier to see in the
high definition radiograph. It can be said that a faithful visual
reproduction of the stepwedge was produced. In the lower
image, the radiographic setup did not produce a faithful visual
reproduction. The edge line between the steps is blurred. This
is evidenced by the gradual transition between the high and
low density areas on the radiograph.