Tag | (2010,0160) |
---|---|
Type | Optional (3) |
Keyword | ReflectedAmbientLight |
Value Multiplicity | 1 |
Value Representation | Unsigned Short (US) |
For scanned monochrome transmissive film viewed on a hypothetical viewing device, the luminance contribution due to reflected ambient light. Expressed as La, in candelas per square meter (cd/m2).
May be used together with Illumination (2010,015E) to recover Optical Density information from P-Values. See Section C.8.6.3.1.
Illumination (2010,015E) and Reflected Ambient Light (2010,0160) may be used to recover Optical Density information from P-Values.
Monochrome media that is being digitized is often measured in Optical Density values. These values need to be converted to P-Values for storage and display. The P-Values used in an image correspond to the perception of a human observer viewing the film on a hypothetical viewing device (such as a light box), using the specified values of Illumination (2010,015E) and Reflected Ambient Light (2010,0160).
The Grayscale Standard Display Function defined in PS3.14 is used to convert Luminance to P-Values. In the case of scanned film, the Luminance is derived from Optical Density using the specified values of Illumination (2010,015E) and Reflected Ambient Light (2010,0160). An example of this derivation, as well as typical "default" values for these parameters, is specified in PS3.14.