radio graphic artefacts
TRANSCRIPT
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THE WELDING INSTITUTE
Radiographic Artifacts
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Light Fog
Light leaks
Caused by: Faulty film cassette, light leaks
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THE WELDING INSTITUTE
Crimping / Pressure Marks
Black appearance crimping after exposure
White appearance crimping before exposure
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THE WELDING INSTITUTE
Film Scratches
Caused by: Mishandling of the film, mechanical damage.
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Static Discharge
Lightening like appearance, but may also be mottled in
appearance.
Caused by: Pulling the film quickly from between the
intensifying screens in a dry atmosphere, causing static
electricity creating density on the radiograph.
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THE WELDING INSTITUTE
Chemical Marks
Caused by: Mishandling of processing chemicals
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Water Marks
Areas of low density on the radiograph
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Dust, Lint and Grime Marks
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Reticulation
Appearance can either be a net like structure or leather
grain.
Caused by excessive temperature variations in the processing
tanks, causing the emulsion to rupture. Very rare artifact today
due to the flexibility of modern base materials and emulsions.
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THE WELDING INSTITUTE
Diffraction Mottle
The appearance is fine porosity or Herringbone porosity
throughout the weld area on the radiograph
Occurs in a radiograph due to the grain size or orientation of
certain materials such as stainless steels and aluminum.
It may be reduced or eliminated by reducing the wavelength
or by changing the radiation angle by approximately 5o