Hey, I'm having trouble working out what Radiance and Irradiance are, all the definitions I get are along the lines of something really technical like:(adsbygoogle = window.adsbygoogle || []).push({});

"For a point of radiant energy, Radiant Intensity, in a specified direction, per unit projected area: Le=(dIe/dA)*Cos(theta) where A is the area and theta is the angle between the specified direction and the surface".

Would you be kind enough to give me a very simple wordy definition of what these are and the difference between the two? Thank you SO much.

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# Radiance and Irradiance.

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