![]() | This ![]() It is of interest to the following WikiProjects: | ||||||||||||||||||||
|
This article is missing the terms for reflectance/reflectivity. What are they?- 69.87.204.232 11:58, 19 May 2007 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on Radiometry. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at {{
Sourcecheck}}
).
An editor has reviewed this edit and fixed any errors that were found.
Cheers.— cyberbot II Talk to my owner:Online 13:23, 23 April 2016 (UTC)
The comment(s) below were originally left at Talk:Radiometry/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
For completeness, this article should define the terms "luminosity", "spectral luminosity", and "spectral radiant flux". I believe that luminosity is the total radiated power in Watts, while spectral luminosity is the radiated power per Hz or per unit wavelength (I'm not sure about this last).
Also, this article would be much more useful if it provided some information about measurement equipment and techniques. P.S. I work mainly with RF, so I'm not really qualified to fill in the above. |
Last edited at 20:57, 22 March 2007 (UTC). Substituted at 03:49, 30 April 2016 (UTC)
On the new radiometer, is it a radiometry understanding that somebody would comment upon here? — Preceding unsigned comment added by 159.100.67.82 ( talk) 11:44, 26 August 2018 (UTC)
[this repeats a comment left in the topic "irradiance".] for purely instrumental reasons and the relevance of physical quantities to questions that measurement is intended to answer (e.g., astrophysics, climatology, workplace safety regulations, etc.) or measurement location (outer space, earth's surface, etc.), radiology metrics do not routinely include the entire electromagnetic spectrum. this is implied by the vague statement that radiology "measures the electromagnetic spectrum." i believe (but do not have sources to cite) that the routine span of measured irradiance/radiance is roughly the optical range 10e-07 to 10e-03 meters, and i am nearly certain that measures such as the solar constant do not rely on actual instrumental measures in the electromagnetic range 10e-16 to 10e8 ish. they are instead either estimates based on fitting a blackbody curve to the measured segment or overlapping/gappy piece curves estimated from different sources using different instrumentation. this applies to all the subtopics in radiology (irradiance, radiance, etc.) where the wikipedist interest seems fixated on the mathematics at the expense of the practicalities. and while i'm quibbling, a paragraph on the actual instrumentation used would be useful, and place the spectral limits in the context of measurement/observation limitations. Drollere ( talk) 15:47, 13 October 2020 (UTC)
The figure in this article implies that , , and This seems like an abuse of notation, since is not actually a function of area or solid angle, and is in fact just a scalar quantity. In reality, accurate relations are surface integrals: , , and .
Similarly, the radiant spectral flux can't be defined as the derivative of the radiant flux, since the radiant flux is by definition is not a function of wavelength or frequency. Again, the correct relation is by a definite integral. 65.60.153.214 ( talk) 22:25, 30 January 2023 (UTC)
More general than the quest for reflectivity this article (and that on photometry) ought to include quantities describing material properties for eg reflexion, scattering, transmission and emission. In radiometry for example BRDF can be used to describe the relation between irradiance and radiance for a surface. BRDF is a multidimensional function describing a large range of conditions. There are probably other quantities of interest too, some relating other quantities to each other, some representing subsets of conditions (e.g. the reflectivity quantity). 150.227.15.253 ( talk) 15:43, 16 January 2024 (UTC)