reading this section you will be able to do the following:
and contrast the differences between radiographs and photographs.
Below are a series of photographs
and a radiograph of the same objects.
are several characteristics of the photographs and x-ray photographs
that are similar, and yet, there are very distinct differences.
Radiography and photography both often use some type of film to
record the image. The principle difference is in how the image
is recorded on the film.
photography, the image on the film is produced due to the reflection
of light. When you want to take a picture, you use a camera, which
has a shutter that opens and closes allowing light to enter and
strike the film. The amount of light that interacts with the film
determines how the image appears on the film .
the process to produce an image is quite different. The camera
is actually a radiation source and it operates quite differently
than a photographic camera. The film is not placed inside the
camera but instead is placed on the opposite side of the object
being imaged. The radiation is not reflected to the film, but
rather passes through the object and then strikes the film. The
image on the film is dependent upon how much of the radiation
makes it through the object and to the film. Some materials like
bone and metal stop more of the radiation from passing through
than do materials like flesh and plastic. The amount of material
that the X-rays must travel through also affects how many X-rays
reach the film. Differences in the type of material and the amount
of material that the X-rays must penetrate are responsible for
the details in the image.
- In photography,
reflected light rays from the object expose the film to produce
- In radiography,
X-rays that pass through the object expose the film to produce
in the types and amounts of the materials that the X-rays must
travel through are responsible for the details of the radiographic