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I am unable to find anything in the literature to back up the claim that appears all over the internet that:

The modern candlepower now equates directly to the number of candelas.

Can anyone please suggest something in the scientific literature to back up this statement?

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1 Answer

up vote 6 down vote accepted

Perhaps this paper is what you are looking for? http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5323103&tag=1

A quote:

The form of primary standard of light (Fig. 1) now in force internationally consists of a black-body (or cavity) radiator held at the temperature of freezing platinum (2042° K). The corresponding unit of luminous intensity is the 'can- dela' (cd). By definition, the brightness or luminance of the radiator is 60cd/cm2. The figure 60 was chosen to ensure con- tinuity, so that, within limits of experimental error at the various relevant dates, an intensity of 1 cd is the same as the older international candle, which in turn was approximately equal to the intensity of the earliest standard sperm candle.

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This definition was valid from 1948 to 1979. The new definition is 1 cd = 1/683 W/sr of monochromatic light at 540 THz. –  Edgar Bonet Jan 11 '12 at 12:53
    
hehehehe, freezing platinum –  Emilio Pisanty Aug 1 '12 at 23:00
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