Where does solarization collide?

In photography, solarization is the partial or complete reversal of an image's tones caused by gross overexposure of the emulsion, so that the most heavily exposed highlights come back lighter instead of darker and the characteristic curve bends back on itself beyond its peak density. Carroll's 1925 Solarization and photographic reversal of desensitizers studied the effect in silver-halide emulsions, and Jolly's 1991 Solarization: The photographic Sabatier effect distinguishes true solarization from the Sabattier effect, the darkroom technique of briefly re-exposing a developing print to light that mimics the look. The referent is a reversal of photographic density in a light-sensitive layer, and it has nothing to do with heating soil or darkening glass beyond the shared root of being overdone by the sun.[1][2]

Unit

The exposure beyond which developed density falls rather than rises

Recovery means

Not applicable

Measured by

Read from the reversal, or turn-down, of the characteristic curve of density versus log exposure at very high exposures

In agriculture, solarization is a non-chemical control method in which moist soil is covered with transparent polyethylene during hot months so that trapped solar radiation raises soil temperature enough to kill soilborne fungi, nematodes, weeds, and other pests. Katan's 1981 Solar heating (solarization) of soil for control of soilborne pests set out the practice and the thermal thresholds that make it work. The referent is a thermal disinfestation of a field, measured by pathogen survival and soil-temperature profiles, and it is an entirely separate construct from a reversed photographic image or a yellowed lens, sharing only the meaning of being driven by the sun.[3]

Unit

The soil temperature and exposure time that suppress soilborne pests

Recovery means

Not applicable

Measured by

Assessed by soil-temperature profiles under the tarp and by pathogen, weed, and nematode survival after treatment

In glass and optics, solarization is the darkening or change in transmission of a glass under prolonged ultraviolet or ionizing radiation, as the light generates color centers, point defects that trap electrons or holes and absorb visible light where the fresh glass was clear. Zolotkov and colleagues' 1986 Color centers and the solarization of UV glasses traced the induced absorption to these defects and the impurities that seed them. The referent is a radiation-induced optical degradation of a solid, measured by the loss of transmittance over time, and it is unrelated to a photographic reversal or a treated field beyond the common thread of sunlight doing the work.[4]

Unit

The drop in optical transmission a glass suffers under UV dose

Recovery means

Some solarization anneals out with heat; the term marks the radiation-induced loss, not a permanent state

Measured by

Tracked by induced-absorption or transmittance spectra before and after a measured UV or radiation dose