I have started a discussion thread in the past about a comparison between Radiance and other rendering engines, but this time, I wondered if anybody had any specific experience with Autodesk Insight and Sefaira? These two differ from artistic rendering engines in that they claim to use the same lighting model as Radiance (with a simplified daylight model) in the case of Insight, and perhaps they just use Radiance in the case of Sefaira.
In particular, this is the introductory webpage about Insight and their daylighting services:
I have copied some of the more intriguing claims:
The Rendering setup uses the same daylighting and electric lighting models that are used for the visual rendering for the time being. While the electric light model is the same as Radiance and other industry standard tools, and uses the fixture and lamp photometric models, if included, the sun light (daylight) model is slightly simplified. To be consistent for visual renderings, the sun light (daylighting) distribution is modeled using the Preetham sky model, which assumes a clear sky and no aerosol effects like fog or haze. The underlying algorithm for this model is similar to the more advanced Perez model, but the heuristics assume standard solar response and therefore do not use solar radiation or illuminance values from a weather file.
In another article coming to this site in a couple weeks, we will talk about the technical validation work that has been done on the illuminance output from the Autodesk 360 Rendering engine. For the moment, we can say that the engine has been validated with the help of one of the top daylighting firms in the country by comparing our cloud rendering output using the same model rendered in the industry standard lighting simulation tool Radiance, as well as to the actual space measured in the real world.
Results of the validation tests are strikingly similar in all ways but one…the time it takes to create the rendering. When we asked about the level of quality used in the Radiance rendering and how much time it took, the answer was: 5 bounces and it took about 4 hours to render. When we asked the cloud rendering technician how many bounces, the answer was ‘all of them’, and the rendering took about 10 minutes .
As for Sefaira, here is some related reading I found:
Any thoughts and the above two products and how they compare to a usage “vanilla” Radiance?