The Radiographic Image
Course Number: 571
Image Magnification
It refers to the proportional increase in the dimensions of a radiographed object relative to the actual dimensions of that object and depends on the following factors:
Increasing object-to-film distance only will increase the magnification of the radiographic image. Reducing object to film distance only will result in a decrease in magnification of the radiographic image (Figure 8)2,4,7,8
Comparison of magnification when the object to film distance changes. A short distance (A) shows less magnification than a long distance (B).
Increasing source-to-object distance only will decrease the magnification of the radiographic image. Decreasing source to object distance only will increase the magnification of the radiographic image (Figure 9).2,4,7,8
Figure 9.
Comparison of magnification when the source to object distance changes. A short distance (A) shows more magnification than a long-distance (B).