My big issue as a rendering newbie when making studio-style shots was how to get a certain background gradient or solid colour quickly and independently of lighting the actual product.
My previous Brazil tutorial showed a method that works well when looking for a reflection in the 'floor' but was a little elaborate.
To start with this little duck, here's the simple gradient environment that I want to see. It's lit only with global illumination from the environment.
Here it is with a Global Illumination environment, one of the 'Studio' HDRIs included with Brazil.
Now the gradient background is what you see, but the GI environment is providing the lighting and reflections. There is more than one way to do such 'overriding,' but in this case I combined them using a Composite Environment. The GI environment was simply plugged into the first slot and the gradient into the second.
So that the duck doesn't appear to be floating in space, I add a plane.
And finally, the plane is assigned a Matte material. It makes the surface 'invisible' but it still receives shadows (and/or reflections,) and those shadows make the duck appear to actually be sitting on the background.
Buy Brazil here.
