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1900 Astrophysical Jrnl. 11 91 In a simple experiment with the aid of Scheiner's sensitometer equal degrees of blackening were produced by continuous exposures of 96, 72, 48, 24, 12 secs.

1900 Astrophysical Jrnl. 11 98 Remarks on the Scheiner sensitometer.

1911 A. Watkins Photography (ed. 5) iii. 47 In the case of Wynne, Scheiner, and Warnerke numbers..there is not the same direct proportion between the numbers.

1911 A. Watkins Photography (ed. 5) Index 332 Scheiner speeds.

1918 J. R. Roebuck Sci. & Pract. of Photogr. 225 ‘n’ is the Scheiner degree and ‘A’ has the value in this case of about 4·4.

1936 Discovery June 192/2 The rating [of the exposure meter] agreeing more or less with the Scheiner system.

1938 S. G. B. Stubbs Mod. Encycl. Photogr. II. 1105/1 The so-called ‘Scheiner speeds’ quoted by Continental manufacturers are in reality not Scheiner speeds at all, as all ‘Scheiner’ measurements are now carried out by the Eder–Hecht method.

1942 C. B. Neblette Photogr. (ed. 4) xiii. 419 The ratio of the exposures between consecutive steps on the Scheiner sensitometer is as 1:1·27.

1962 C. B. Neblette Photogr. (ed. 6) xx. 267/1 The Scheiner speed number was obtained originally by exposing the negative material in a sensitometer with a sector wheel having exposure steps numbered from 1 to 20, with a log exposure difference of 0·15.

1962 C. B. Neblette Photogr. (ed. 6) xx. 267/2 In 1931, the German photographic industry replaced the then meaningless Scheiner numbers by a new German standard (DIN) speed.

1963 H. G. Jerrard & D. B. McNeill Dict. Sci. Units 106 The Scheiner scale was devised in 1898..and was first used commercially by the Secco Film Company of Boston, Mass. in 1899.

1973 Focal Dict. Photogr. Technol. 544 Scheiner speed was expressed in degrees, every increase of 3° corresponding to a doubling of the working speed.