Image based lighting often times simplifies getting started with a good lighting setup when trying to integrate CG into life action. Often times it’s beneficial to have the IBL sphere to just contain the ambient lights from the environment and therefore to paint out any actual light sources from the set. Those can then be used on separate lights to give the main illumination from the set lights, while the IBL sphere contributes ambient environment light. Now, if you have a lot of different environments and consequently a lot of different HDR’s it can be tedious to paint out the lights and output them after that…
