History of Radiographic Film Processing

Radiography is also known as x-ray imaging. X-rays were first discovered by Wilhelm Conrad Rontgen, a professor at Weurzburg University in Germany in 1896. His experiments proved the existence of a previously unknown type of electromagnetic ray that could pass through heavy paper. Additional testing showed the rays could pass through many objects, leaving a shadow. Most importantly, the rays could pass through organic tissue but not bones. When a photographic plate was put behind the body part having x-rays sent through it, the bones blocked the rays and hence didn't mark the plate, while the rays passing through tissue did.

Early Uses

• With the discovery that x-rays could be used to see through things, a world of uses opened up for them. The earliest applications were industrial, such as examining steel parts and checking on welded pressure vessels, but it is the medical uses where radiography continues to be used. Surgeons used radiography to guide their work, such as finding bullets in wounded soldiers.

Additional Discoveries

• Natural radiation was discovered in 1896 by Henri Becquerel, a French scientist. It was also found to be another penetrating ray when wrapped photographic plates placed in a drawer with uranium were accidentally fogged. Two years later, the Curies discovered radioactive radium and polonium.

New Uses

• Because radium and polonium were more powerful than x-rays, new uses were developed for radiography. Material castings up to a foot thick could be radiographed, which was an aid in the shipbuilding industry. Photographic plates placed behind the castings allowed any flaws to be mapped out by the shadows left on the plate.

Dangers

• Years after the discovery and use of x-rays and radiation for radiography, scientists began wondering about potential dangers. These were new technologies that seemed to do no harm. As scientists began to be unknowingly injured or sickened by x-rays and radiation, scientists at first didn't realize the connection. By 1942, scientists were searching for ways to protect against the harmful effects of radiography.

Modern Radiography

• While radiography still works by capturing shadows on film, the quality of the images has improved through better machinery and higher-sensitivity film. Film processing is an automated process nowadays, which helps ensure consistent high quality. New technologies using computers mean that film is not even needed in some cases. Radiography is still used industrially to inspect welds and casting. It is a staple in the medical industry as well. However, it is also part of modern security with the new body scans that some airports are using and the older technology of searching sealed baggage.