Talk:Visibility

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It is not "Intensity", It is Luminance[edit]

In the Derivation part, FB(x) and F(x) are not intensities. They are luminances! And the reason the equations come in that form is due to an assumption: the attenuation coefficients for lights with different wavelengths are the same. — Preceding unsigned comment added by 222.18.127.124 (talk) 13:10, 14 October 2013 (UTC)

Bug report: disambiguation[edit]

Sorry for not fixing this myself, don't have time at the moment, but maybe this comment will help: This article doesn't link to uses of the term 'Visibility' in any field except meteorology. There should be some disambiguation, either on top of this page or on a separate page. —Preceding unsigned comment added by 86.59.11.23 (talk) 01:32, 5 August 2008 (UTC)

New Contrast Standard?[edit]

Multiple sources that I've found (e.g. this one) suggest that 5% is a more appropriate contrast threshold making the "modern" value for Koschmieder's equation 2.99/bext. I'm not an expert on this subject and did not feel comfortable changing the page, but it appears that perhaps someone should. — Preceding unsigned comment added by CoryCohen2 (talkcontribs) 02:39, 2 December 2016 (UTC)

Background Intensity Constant?[edit]

Why is it stated that F(b) is constant? I would think the white background also changes in its intensity as we move away from it. Are the distance from the observer to the object and observer to the background the same? What is the background composed of? — Preceding unsigned comment added by 137.75.200.138 (talk) 00:53, 14 December 2016 (UTC)

Measurement methods[edit]

Information on how visibility is measured, especially by automated means might be useful.... http://www.nws.noaa.gov/asos/vsby.htm seems to be a potential public domain source for at least one method.... Other (non-PD) sources: http://www.metoffice.gov.uk/guide/weather/observations-guide/how-we-measure-visibility http://www.wral.com/weather/blogpost/3095296/ (Interesting, the manual methods seems to vary between the US and UK, UK takes lowest value, US seems to take the greatest value for more than 50% of the directions) MoHaG (talk) 09:10, 11 January 2017 (UTC)