Baggin's - if you are using this as a fill light - no probs on the other light sources. However, you'll need to get shadows setup on your standard lights - since the AO from the IBL will be very weak (as show in your render above) due to it's low intensity relative to the other lights. If rendertime is no option, can I recommend depth mapped shadows, 0.01 bias, blur 10-20 (depending on the light you are trying to simulate), map size 3072 (very important). If rendertime IS important, you'll need to live with smaller shadow map sizes (1024). Mmmmm, we've strayed a little off topic here....

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