Real world units for Corona Light Material

[Cinemike]

As topic says - Lumen would be welcomed there :)

[houska]

Thanks for the suggestion, Mike!

Unfortunately, this seems like a rather problematic thing from the perspective of user intuition. Now, I suppose you know the definition of 1 lumen, but just as a reminder for others - lumens are a unit describing total luminous output of a light source. If we allowed to set lumens as units for Corona Light Material, the actual luminosity of each light emitting object with this material would have to adapt to the size of the object.

Now, what would definitely make sense is allowing to set lux, candelas or Watts per meter squared but those are obviously not so intuitive anymore, as they are not used so much in real life.

[Cinemike]

... the actual luminosity of each light emitting object with this material would have to adapt to the size of the object.

But the same applies to area lights already as well, doesn't it? When they are shown in the render, depending on their size, their visible brightness changes with a constant lumen value.
Lumen could be an optional unit additional to the "default" one.

PS Vray's luminous material does have units, too (also "Lumen").

[Cinemike]

Another PS: I would not mind having Candela for flames either :)

[houska]

Yeah, but with the Corona light, it kind of makes sense, because what you're setting through the UI is the total luminous flux of the given light source. However, with the material, this notion does not make any sense if you only take into account the material itself.

[brankonovakovic]

In Corona V5 for c4d is resolved.

[Cinemike]

Sorry, not resolved.
I was asking for the Corona Light MATERIAL, in the Corona Light OBJECT it has been existing forever.

[houska]

Yes, and in the Corona Light Material, it's simply nonsense to have Lumens, as pointed out earlier ;-)

[Cinemike]

I accepted that. But it's not resolved :P

[Cinemike]

Besides ... the discussion reminded me of the Vray material window ...

[houska]

Besides ... the discussion reminded me of the Vray material window ...

Yeah, don't get me wrong, I'm not trying to be smart or anything, but this is the first line of the entry on Lumen from Wikipedia (emphasis added):
"The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the total quantity of visible light emitted by a source per unit of time."

So how in the world can a material with a total luminous flux of 1500 Lumen work?? Will it spawn a different material per each object it's assigned to, based on the object's size? Or will it calculate its intensity according to a reference surface (let's say 1m^2)? In both cases, I can imagine a lot of surprised (and angry) users :-)

Edit: As I said - watts per steradian and meter squared - sure! Candela - why not?! But I'm not convinced it would make physical sense to have Lumens...