Big discrepancies between annual DGP calculation and DGP from image

Hi all,

I am calculating the annual DGP for a given model from a certain point (attached file “glare example step 1”), from that calculation I figure out wich hour thoughout the year produces the highest DGP. Then I simulate the ilumimance image for that specific date, in this case the 1st of june at 08:00 (attached file “glare example step 2”) to locate the glare patches. The problem is that the DGP value I get in the second simulation (0.22) is much lower than what the annual simulation predicted (1.00).

Am I doing something wrong? Shouldn’t both simulations throw similar (if not identical) results?

Thanks in advance


glare example step (489 KB)
glare sxample step (487 KB)

Hi Alejandro,

Every time that I show annual glare ti someone I warn him/her about the annual glare analysis and encourage them to cross reference the results. I don’t think it’s a mistake from your side. I have seen discrepancies too and stopped using the annual glare analysis but maybe both of us making a mistake!

Have you tried to plot the annual results in 3DChart? Does it show a reasonable pattern?

I would say this is a great question for Daysim email list. Jan is on the list and should be able to tell us why this is happening.


Thanks Mostapha,

The annual parttern does make sense. It shows though a lot of ones, so it is hard to find out which of these ones would be the annual maximum. Yes, it would be good if someone from the Daysim mailing list would be able to give us an answer on this.

Thanks for a quick answer.


Hi Alejandro and @mostapha ,
how do I get DGP for the entire year by using HB legacy? How can I create an annual carpet plot?
Thank you very much.