Talk:Diffuse reflectance spectroscopy

message: I've been translating material on spectroscopy - in connection, specifically, with pigments - for decades, and all the authorities on this subject, not to mention the good dictionaries (there are also some bad ones!) refer to this as "reflectance" or "diffuse reflectance". The German word is "Remission" - I suspect the English word is not! Maelli (talk) 21:23, 7 December 2014 (UTC)
thread_title:  Suspect a false friend (otherwise known as lazy translating) 

message: The following is from:  "Glossary of Terms used is Vibrational Spectroscopy" by John E. Bertie in the Handbook of Vibrational Spectroscopy;  edited by John M. Chalmers and Peter R. Griffiths; John Wiley & Sons Ltd, Chichester (2002).
Remission: The process by which radiation that is incident on one side of a scattering sample is redirected to leave the sample on the same side; often called diffuse reflection.
The English origin of the term "Remission" is not a "lazy translation".  As the article suggests, the term has a Latin origin, so it is not surprising that other languages use it.  The term "Diffuse Reflectance" was in wide usage in the 1960s.  If one looks at two classic books from that era (both named "Reflectance Spectroscopy", [Wesley Wm. Wendlandt and Harry G. Hecht; Reflectance Spectroscopy; Interscience Publishers, New York, NY (1966])] [Gustav Kortüm, Reflectance Spectroscopy; Springer-Verlag, New York, NY (1969)]; one sees that "regular reflection" and "diffuse reflection" were given two different theoretical treatments.  Apparently the authors believed that the two could be separated for spectroscopic purposes.  This is no longer the accepted view.
Since the term Diffuse Reflectance is more widely used than the term "Remission", we entitled our 2007 book: Interpreting Diffuse Reflectance and Transmittance; Donald J. Dahm and Kevin D. Dahm; IM Publications, Chichester, UK (2007).  However, on the inside we used the term "remission",
 
Our Definitions (pages 207 to 209)
Backscatter:  As we use the term, backscatter refers to light that has been transmitted through one or more particles, reflected from an internal surface and is transmitted through any particles encountered on the way back to the detector. 
Reflection:  Regular reflection of light from a surface: For reflected light, the angle of incidence equals the angle of reflection. The intensity of reflected light is described by Fresnel’s formulas. In order for a surface to reflect, it must be large compared to the wavelength of the light striking it.
Reflectance, Diffuse Reflectance, Diffuse Reflection: These terms are widely used as referring to the
sum of reflection and back-scatter. We have tried to avoid using them, favoring the use of remission.
Remission:  Processes that result in light leaving a sample traveling in a direction which has a component in the opposite direction as the incident beam.
There is another problem with using the term "reflection" in that some of the light that is reflected from a surface of a particle can be transmitted by a sample (page 24). So all in all, remission seems to be emerging as the preferred term.
 
DJDahm (talk) 15:10, 24 November 2016 (UTC)
thread_title:   "Remission" versus "Diffuse Reflectance"