Hi. Thanks for your reply and advice. I changed the FG settings low. Accuracy: 50, density 0.5. Also frame buffer back to 1. The problem is, i dont have a light in the scene. The only thing i use is FG and the Image Based Lighting (the built in option) sphere.
I changed the floor to a plane with white colored lambert. Turned off cast FG, and visiblty on reflections.
Now i get this grey background and white floor. The reason i get this grey background is bec i created a grey background image in HDRI light studo 2.0.
In maya i try to set the color offset value of IBL, to pure white from black. But this time i get blown whites on sphere.
By the white hue i mean, theres a white reflection on the second image i posted. And at the bottom of the sphere theres a white highlight at the borders. (Shouldnt it be black?) I am confused.... I need to solve this white background photorealistic image lighting soon. Hope we can solve this : /