Problems setting up semitransparent media

Tim

hello, is there anybody who can explain to me wich wave lenght intervalls i should type in in the do-model pannel (radiation model - diskret ordinate) if i want to model sunlight travelling through a window and then heating up air in a shaft with a black backplane. Also i dont know which settings sould be made in the wallpanel for the semitransparent vitrification, if i want the radiation to fall in perpendicular to the window. Give me some tips or maybe you know where i can find informations about my problem. thank you Tim