I am sure you have seen those false color images that describe the light distribution in a space,
usually to help lighting designers. We are very happy to announce now that this feature has
been added in Thea!

These false color images actually describe the luminance and illuminance distribution. Thea Render
can compute now both of them; luminance is computed out of the box for any image that you
have already rendered and for any render settings. Illuminance can be computed by the Adaptive
BSD engine - as a byproduct of the irradiance map. In addition to the false color rendering,
user can select regions of interest, find the extreme points and check the distribution of values
with the available histograms.

But we didn't stop there! We developed another add-on, where Thea can produce a html report
that you can easily share! Please, check the screenshots below.

We are very glad to see this coming out with our next public revision, a feature available in expensive
applications but now with the accuracy and fidelity of Thea.

Thank you! This is great...remember it from Lightscape. Is it accurate like Lightscape used to be (radiosity)? Could it's numerical results be used in lighting design documentation, or just as roughly conceptual tool?

Hi Giannis, and thanks for this nice feature ! I have a little question about it :

is that feature will be possible to use with IR, because combined with the region option it could be great in order to tweak lights !?

Forgive the stupid question, but what are the practical applications of this tool?

It is especially good for those who design lighting and architects. If you use IES lights from lighting manufacturers you can easily tell whether they will lit a room efficiently in reality. For example - work surface should have illuminance of 200 lm/m2 (=lux) ≅ 20 lm/ft2.

Yes, it is quite accurate; the luminance computation especially the one taking place by the unbiased engines, is as accurate as it can be. The illuminance depends on the tuning of final gathering which can trace more than just diffuse interreflection; in addition, photon map caustics can be added, a feature also missing from traditional radiosity solutions.

@Panga: luminance false color image can shown by IR; illuminance is only computed by BSD (in darkroom).

The false color rendering, is an easy way to find high energy areas (perceptually) in your render and vice versa, dark areas that need to be illuminated better. Lighting design and engineering is a whole art on its own, such a feature can give a good visual and numerical help when making decisions.

best wishes

I hope to someday be advanced enough to understand what this even means I love it though.

The false color images are a nice effect. I'll probably use it one day for some cool effect.

From the lighting side I kind of thought this could have been done before by looking at the full color picture and seeing the hot spots in the image. I guess this makes it easier when exact brightness is critical. For the lighting to be the same it would seem that having an accurate material becomes all the more critical. If the reflection or diffuse is off then the exact brightness of that object with that lighting will not be the exact same as it would be in real life. Correct me if I'm wrong on any of this.

Thanks for the explanation Tomasz

Waw, fantastic news Giannis!!
Unexpected and great to finally have a good (and usable) Radiance-like renderer in the field. Thanks a lot!

And yes, it can come in very handy for office / school / ... design, where certain workspace illumination is needed.