appleseed Users Forum

Radiance Conference Room

Finally I found some time to convert the Radiance Conference Room scene to the latest appleseed release. I used the latest blenderseed release for Windows and you can download the .blend file here (conference_room/blend/conference_room_appleseed.blend) if you want to play with it. There should be several cameras defined in the scene (see Arnold version with shaders simulating the Radiance .cal files). Simply switch to a camera and press F12 (the render button).


Hi Jan,
Thanks for the scene posting. It’s always great to see comparisons with other render engines, especially when it is with so many different engines as you did.

We have an appleseed scene pack with conversions of many of Benedikt Bitterli’s Resources for testing. If you haven’t already done so please join our Discord server where you get access to newest builds and other resources along with lively discussions about all render related things.


Some comments for visitors of this thread who maybe not familiar with this scene.

This conference room scene is a famous recreation of an actual room to study the exact radiation distribution with a software called Radiance.
The emphasis of Radiance is not on the visual/artistic aspect of render engines used for archviz scenes like Corona or V-Ray and therefore may not look as stunning as your usual indoor archviz scene.
But unique to Radiance is that it is painstakingly verified for exact numerical accuracy. The tool is used the world over for lighting simulations by lighting engineers when they want to predict how a space will be lit, either through natural or artificial lighting.

Radiance has been compared to other lighting calculations, scale model measurements and real spaces to validate its capabilities. No other lighting calculation has undergone a more rigorous validation.

For us the benefit is that we can compare appleseed’s render output with the calibrated one from Radiance. appleseed strives also for accurate light transport and predictive rendering capabilities when set to unbiased mode.


Two questions:

  1. How easy is it to write shaders for appleseed? I did this once for the Arnold renderer (based on Radiance’ .cal files).
  2. What are the Radiance .dat files? E.g. 325-AL97-248RS.dat used in the original Radiance scene. Are they like IES files?

Would be cool to take this a step further and apply IES files to the light emitters and replicate the materials (procedural textures).

It’s very easy as we use OSL which is fairly intuitive if you know C/C++:

Some other links of interest:

No idea.

It would! Note that appleseed doesn’t yet support IES light profiles, although we have started working on it (the parsing code is done but the light model has yet to be implemented).

We’re welcome all help :slight_smile:

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