Differences in sun position (Radiance vs Dialux)


I have created two identical room models in both Radiance and Dialux in order to simulate a clear sky condition. Both models have two ceiling-high daylight openings with glazing in the corners of the façade. I have compared the illuminance result and it seems the sun position in both software is different. For your information, both models have the same date, time and location. Can you help me to find out why the sun position is different in both models?

Seems to be that there is one hour shift.
This topic has widely discussed (even recently), so do some quick search in this forum.

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@AbrahamYezioro thanks!

However in my case half an hour time shift!

It is according to the resolution of your time step.
As i recall LB Legacy has this shift and LB[+] doesn’t (is just a programming thing].
You need to adjust either of both softwares you are using to compare fairly.

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The following question:

While comparing illuminanace values using Dialux and Radiance (with an overcast sky), I am experiencing lower values for Dialux on a set of grid points. Did you have experience with such a situation?