An object seen on an X-ray may have been magnified during the imaging procedure. The actual size of the object can be estimated based on the final image size and the radiographic setup.


actual measurement of object dimension in cm =

= (distance from the X-ray tube to the object in cm) * (measurement of image on the X-ray film in cm) / (distance from the X-ray tube to the film in cm)



• The usual distance between the X-ray tube and the film is 6 feet.

• Under most conditions the maximum magnification for an object will be about 1.25 times actual size.


If the object is noted in a lateral view to be very close to the film, then no magnification will have occurred and no adjustment needs to be made.


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