Difference in daylight factor result mesh

Hi! Could someone explain why do I get this strange result mesh when I run the daylight factor simulation the second time? I don’t get any errors. For some of the smaller rooms the average daylight factor is much higher than in the first simulation.

The files are saved here:
https://drive.google.com/drive/folders/1AHj1_CDM8BxBW6NSzCG6N-gKNBO0BTeO?usp=share_link


Hi @zahabia - have you added a lot of context buildings to the simulation in your second image?

It looks like the ambient resolution needs to be adjusted - there’s an ambient resolution component you can input into radiance parameters component

As far as I understand, the two are operated with different Radiance parameters. Probably the analysis process of the first image took longer. So, at least in my own studies, when I run it with different parameters, I get different results in this way.

Hi! Yes, I did add a few more context buildings. I also tried to run it with a higher resolution but then the results are quite different and it takes 10 hours! The first analysis took 3 hours.

How do you decide what kind of radiance parameters to choose? I usually go with detail level 2 and change the ambient bounces when the room is deeper.

The radiance parameters are the same. I just simplified the geometry in some parts and added some context buildings.

Hey @zahabia,

You can leave the detail level for radiance parameters the same, the crucial parameter you need to adjust is the ambient resolution

If you search the forum there’s a few posts about it, I gave a bit of an answer on it to someone else here

I’d recommend running at low detail level to start with and adjust the ambient resolution parameter (using the ambient resolution component and inputting your model and adjusting the detail level) initially to check the result pattern makes sense. Then you can increase the detail level to get a more accurate lux level / daylight factor result.

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