AS ISO 12232:2019 pdf free

AS ISO 12232:2019 pdf free.Photography一Digital still cameras一Determination of exposure index,ISO speed ratings, standard output sensitivity, and recommended exposure index
The reported values shall indicate whether illumination approximating the ISO 7589 daylight or studio tungsten illuminant was used. ISO 7589 describes the procedures for determining if the illumination used in a specific speed rating determination test is an acceptable match to the daylight and studio tungsten illuminants. Also, the spectral power distribution of the illumination used should be reasonably similar to that of the ISO 7589 daylight or studio tungsten reference illuminant.
For daylight measurements without the camera lens, the ISO sensitometric daylight illuminant given in ISO 7589:2002, Table 1, shall be used. This illuminant is defined as the product of the spectral power distribution of CIE colorimetric standard illuminant D55 and the spectral transmittance of the International Standard camera lens. For measurements with the camera lens in place, the spectral radiance characteristics of the light used for the measurement should be equivalent to the daylight ISO standard source provided in the second column of ISO 7589:2002, Table 1. In order to apply the ISO SDI (spectral distribution index) criterion, the spectral radiance of the light shall be measured and then multiplied by the relative spectral transmittance of the ISO standard lens, which is also described in ISO 7589, prior to multiplying by the weighted spectral sensitivities.
For tungsten measurements without the camera lens, the ISO sensitometric studio tungsten illuminant given in ISO 7589:2002, Table 2, shall be used. This illuminant is defined as the product of the average spectral power distribution of experimentally measured sources having a colour temperature of approximately 3 050 K and the spectral transmittance of the International Standard camera lens. For measurements with the camera lens in place, the spectral radiance characteristics of the light used for the measurement should be equivalent to the tungsten ISO standard source provided in the second column of ISO 7589:2002, Table 2. In order to apply the ISO SDI (spectral distribution index) criterion,the spectral radiance of the light shall be measured and then multiplied by the relative spectral transmittance of the ISO standard lens, which is also described in ISO 7589, prior to multiplying by the weighted spectral sensitivities.AS ISO 12232 pdf free download.