could someone explain to me what a Candella is? I am not really getting it.(adsbygoogle = window.adsbygoogle || []).push({});

Okay, so it is a Watt/Steradian. Okay.

Lets say that when we get a flux of 100 photons passing through a surface per second, that that is equal to one watt.

So if we have, lets say 50 Candella, we have a flux of 5000 photons passing through a surface whose area equals r^2 per second.

What I do not get, is, if the Candella is defined this way, then doesn't that mean that the candella is dependent on r? If I were to double r, then i am quadrupling the surface area, and therefore my Candella will go down to a quarter its previous value.

So what does it mean, when you say a lamp has a candella rating of X, without giving the r that was used to determine that?

I mean, if I choose a big enough R, I could get the sun to have a candella of 1E-1000

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# Could someone explian to me what a Candella is?

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