sensitometry

chemistry

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July 13, 2026

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Sensitometry is the science of measuring the sensitivity of photographic materials or the human eye. It involves using an instrument called a sensitometer to give a material a series of graduated exposures. After development, the density of the silver deposit from each exposure is measured and plotted on a graph against the logarithm of the exposure. This creates a characteristic curve, also known as a D/log E curve or H&D curve, which illustrates how the material reacts to changes in exposure. This curve is used to calculate film speed according to international standards like ISO. The term "sensitometric" relates to or is used in sensitometry.12345

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technology of photography
Sensitometry and speed
The sensitivity or speed of a film determines how much light it needs to produce a given amount of silver on development. Sensitometry is the science of measuring this sensitivity, which is determined by giving the material a series of graduated exposures…
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The sensitivity or speed of a film determines how much light it needs to produce a given amount of silver on development. Sensitometry is the science of measuring this sensitivity, which is determined by giving the material a series of graduated exposures…
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speed
Film speed indicates the sensitivity of a particular emulsion to light. It is usually expressed as an ISO (International Standards Organization) number (formerly called, and identical to, the ASA [American Standards Association; now American National Standards Institute] number), or, in Europe, as a DIN (Deutsche Industrie Norm) number. A…
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Film speed indicates the sensitivity of a particular emulsion to light. It is usually expressed as an ISO (International Standards Organization) number (formerly called, and identical to, the ASA [American Standards Association; now American National Standards Institute] number), or, in Europe, as a DIN (Deutsche Industrie Norm) number. A…
Read More