Negative illuminance values

Hello, everyone.

I simulated the illumination value of the desk by the fixed louvers.

I used “Anual Daylight recipe” as shown in the picture and set ab to 8 in the Radiance Parameter.

But I’m getting negative value from a lot of illuminance

So I have a few questions.

  1. Is there a reasonable way to adjust the illuminance value when it is negative?

  2. Is the recipe wrong? Is the 3 phase method or 5 phase method better?
    (Note that negative values were also found in DC recipe.)

Thank you for your answers.

[HB+] Annual illuminance simulation test.gh (550.9 KB)

This is discussed here before.

@devang Hi devang

I saw this post before.
I saw this post and understood the approximate calculation method.

But I didn’t even set ab = 0 like this post.

Can I know how to change the illuminance value to positive?

And in my case, is it right to simulate with 3 or 5 phases?

Hello, I have the same problem. How did you solve it finally