External illuminance

I’m working on daylight analysis at different dates and times in an interior. I have set up the necessary circuit and I am getting results. But how can I output the outdoor light in klux at the specified location, date and time? Which component can give me this output? I would be grateful if you could help.

This question is very vague. Can you say what recipe you are using and how the results that you’re currently getting are different than what you want to get?

I watched a tutorial (2 - Getting Started With Ladybug - Visualizing Data on the Colored Chart - YouTube) and found the answer to my question. Thank you for both the answer and the tutorial.

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I am trying to reach the illuminance value in the room by using the HB Point-In-Time-Grid component. But I need the external illuminance value for efficiency. For this, I can read the direct normal, diffuse horizontal and global horrizontal values by connecting the importEPW component to the LB HourlyPlot component. Which of these values does PITGrid use?

None of them. All of the Radiance recipes actually use the “Direct Normal Radiation” and the “Diffuse Horizontal Radiation” data from the EPW in order to run daylight studies. Not the illuminance. Radiance has built-in sky models that account for the luminous efficacy under various conditions.

I know. I also thought it was weird the first time that I learned this. But, long story short, trying to do a direct comparison between EPW illuminance and the output of Radiance might not be a perfect match but they should be pretty close.