FANDOM


FFD

Focal-film distance (FFD)

About

Focal-film distance (FFD) is the the distance between the center of the anode of the x-ray tube (the focal spot) and the film (top of cassette). Also known as, Source-image distance (SID) which this measurement effects magnification, distortion, and x-ray beam intensity. To assist with reducing these types of negative effects, we only use two FFD types, a long distance (70 cm) and a short distance (40 cm). The short distance is most commonly used for all xray tests, calibration verification, and alignment procedures.[1]

References

  1. Thomas. Patrick. Jr. "Basic Radiograpghic Procedures". p. 3. http://chiro.org/radiology/ABSTRACTS/procedures.pdf

Links

Ad blocker interference detected!


Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.