Timeline for Why isn't a BRDF a ratio of radiances?
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
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| Nov 28, 2021 at 18:44 | comment | added | Sam | @cifz Saying that irradiance is incoming and radiance is outgoing light can be very misleading for beginners as it begs you to draw the conclusion that this is the actual difference between those two terms. In fact, radiance can be incoming and outgoing and irradiance has nothing to do with direction. Its light from any direction hitting a surface (you made that clear in the braces, but it should be emphasized more) | |
| May 11, 2021 at 12:52 | comment | added | akuzminykh | @cifz Irradiance is $W/m^{2}$, it's not dependent on directions. | |
| Jul 28, 2016 at 20:52 | vote | accept | PeteUK | ||
| Jul 22, 2016 at 21:13 | comment | added | geometrian | The short answer is: "because then it wouldn't be bidirectional". It's been a while, but I believe my alternate formulation of the rendering equation works out to be using a 1:1 reflectance function. | |
| Jul 22, 2016 at 19:42 | answer | added | Nathan Reed | timeline score: 15 | |
| Jul 15, 2016 at 21:06 | comment | added | cifz | I would write an answer if I had time, but in a concise way: because of definition. Roughly speaking radiance measure OUTGOING light in a certain direction (or better: radiant flux per solid angle). Irradiance is INCOMING light from a certain direction (or better radiant flux received per unit area. BRDF is describing the ratio of outgoing light to incoming light | |
| Jul 15, 2016 at 9:01 | review | First posts | |||
| Jul 16, 2016 at 5:26 | |||||
| Jul 15, 2016 at 9:00 | history | asked | PeteUK | CC BY-SA 3.0 |