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Paper, 'On a failure of the law in photography that when the products of the intensity of the light acting and of the time of exposure are equal, equal amounts of chemical action will be produced' by William de Wiveleslie Abney

Reference number: PP/22/11

Date: 1893

Description

Abney writes: 'It has been generally assumed that when the products of the intensity of light acting on a sensitive surface and the time of exposure are equal similar amounts of chemical action are produced, and with the ordinary exposures and intensities of light employed such, no doubt, is practically the case, and any methods of measurement hitherto practicable have been insufficiently delicate to discover any departure from this law, if such departure existed. In some recent experiments however, I have discovered that this law breaks down under certain conditions, and I think the fact worthy the attention of those interested in the subject, since it is possible that these conditions may arise with other experimenters.'

Annotations in pencil and ink.

Subject: Photography / Chemistry

Received 13 June 1893. Read 15 June 1893.

A version of this paper was published in volume 54 of the Proceedings of the Royal Society as 'On a failure of the law in photography that when the products of the intensity of the light acting and of the time of exposure are equal, equal amounts of chemical action will be produced'.

Reference number
PP/22/11
Earliest possible date
1893
Physical description
Ink and graphite pencil on paper
Page extent
9 pages
Format
Manuscript

Creator name

William de Wiveleslie Abney

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Citation

William de Wiveleslie Abney, Paper, 'On a failure of the law in photography that when the products of the intensity of the light acting and of the time of exposure are equal, equal amounts of chemical action will be produced' by William de Wiveleslie Abney, 1893, PP/22/11, The Royal Society Archives, London, https://makingscience.royalsociety.org/items/pp_22_11/paper-on-a-failure-of-the-law-in-photography-that-when-the-products-of-the-intensity-of-the-light-acting-and-of-the-time-of-exposure-are-equal-equal-amounts-of-chemical-action-will-be-produced-by-william-de-wiveleslie-abney, accessed on 16 March 2026

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  • Proceedings Papers

    The archival collection known as 'Proceedings Papers' is comprised of manuscripts and occasional proofs of scientific papers sent to the Royal Society which were read before meetings of Fellows and printed in full in the Proceedings of the Royal Society.

    Dates: 1882 - 1894

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