X-radiation (left), activity (middle) and cosmic radiation (right)
Photographic observation is truly the oldest form of radiation detection.
It stood at the brink of the discovery of
X-radiation (see Figure, left),
activity (see Figure, middle) and
cosmic radiation (see Figure, right).
For a long time, photographic emulsions were used for personal dosimetry.
Today, this type of detection has been almost completely replaced by semiconductor techniques.