You searched for: “actinograph
actinograph
1. An instrument, invented by Sir J. Herschel in 1838, for recording the variations in the power of the solar rays.
2. An instrument (of which there are various kinds) used for recording actinic power of light, to determine the correct time of exposure for photographic plates.
3. Either seldom used terms, or obsolete terms, for radiograph and radiography (images produced on film or another sensitive surface by radiation; such as, X-rays or gamma rays passing through an object).