IS method with more then 1 order

Hallo dear Arthur,

I have a question regarding the Image Source component.

I don´t understand why the creation of the Image Source with only 1 order, takes a couple of seconds (even for very complex models), but when I set 2 order, the analysis times become biblical. In many cases I had to stopped the script, because it lasted more than 8-10 hours. I am aware that only one more reflection order in the IS, leads to a substantial increase in calculation, but I didn't expect to be nearly unable to use it.

I know that for the evaluation of the energy criterion, the Raytracing method is more than sufficient, while the IS is more important in the auralization theme, but I would like to use them in combination, but in this way is impossible.

I wanted to ask if this is a factor that can be accelerated in some way.

Only to understand your opininion, what error would it make me if I use for example 3 reflections order in the Raytracing component and only one reflection order in the IS component?

Thanks for your time and my best greetings Arthur