Why 'more or less stopped using ISO'?

Started Feb 19, 2014 | Questions thread
Shop cameras & lenses ▾
crames Regular Member • Posts: 192
Re: Maybe this will help.

xpatUSA wrote:

In the context of Photometry which is where we are (?), brightness is a deprecated word, implying that it's use is unscientific, unprofessional and infra dig. It says here:

"Photometric brightness is an old and deprecated term for luminance.

The physical measure of brightness.

Luminous intensity per unit projected area of any surface, as measured from a specific direction.

Luminance (usually 'L' in formulas) is the amount of visible light leaving a point on a surface in a given direction. This "surface" can be a physical surface or an imaginary plane, and the light leaving the surface can be due to reflection, transmission, and/or emission.

Standard unit of luminance is candela per square meter (cd/m²).
(also called nit in the USA, from latin "nitere" = "to shine")."

From:

http://www.schorsch.com/en/kbase/glossary/luminance.html

"Photometric brightness," does indeed appear to be an obscure term. Another "brightness" is the brightness measurement for paper.

The "brightness" being discussed here (at least by me) is a perception, "the attribute of a visual sensation according to which an area appears to emit more or less light," rather than a photometric measurement. The term is in current use in color science and engineering.

The appearance of brightness has been found to be related approximately to the cube-root of luminance, but complicated by a number of factors.

Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow