What I want to do is to make the plane under the ball to be white which will receive the shadow from the ball and will have the reflection of the ball. My idea was to add Emission node to the plane material and to block the light from it from the influencing the ball (for the ball the only source of the light is a lamp). The color I assigned to all the nodes is white. But somehow the result I get is gray. Could anyone explain me why it is so and how can I achieve desirable result?
You have the terrible habit of leaving inputs of the Mix shader unconnected…
No input = physically undefined, total blackness.
What your world node setup is telling Cycles is this: For all camera rays (“Is Camera Ray” = 1) use the bottom input of the Mix shader (white background). For all other ray types (“Is Camera Ray” = 0) use the top input (nothing = blackness).
So, for reflection rays, glossy rays, diffuse rays etc. the world is a pitch black nothingness. And that’s exactly what you see reflected in the floor plane.
IkariShinji, the result of the render I want to get is the next:
Only the ball and its reflection and shade are visible. The background is white. The ball must be lit only by the light from the lamp (and maybe by the light reflected from the plane).
To achieve this result I added the plane (glossy (for reflection)+diffuse (for shade)+emission (to make the plane white)). Also I changed the environment light to white and prevented it from influencing the objects in the scene.
As I said, this will be extremely finicky to set up if you want to avoid compositing.
And the use case for this material will be extremely limited: As soon as you use emission on the plane material you risk to blow out subtle shadowing information. And if you add glossy, you will never be able to use anything other than a pure white environment as the plane will not only reflect the object, but the environment, too.
I’m not saying this is not possible, I just doubt it is sensible to restrict yourself to a render only solution, when everything in this situation cries compositing.
Its a bit of a hack, But it lets you have a shadow on the floor, and a reflection. This is a byproduct of my trying to find a way to render a high glossy shine on boots.
its also caustic friendly, And use the add shader. not a mix shader for this. Think of this has polished wax on a floor. You have both the wax and the floor under the wax adding too the image you are seeing.
You might want to consider area lighting and turn shadows off for it, There is some workarounds for proper lighting, But they tend to be ether convoluted or chew render time. I have not played with it this way but you might try a mesh under the floor that you use as a light, and adding a little translucent too the floor as well. But I’m not sure what the exact thing you are going for is. If you can think of a real world example of what you are trying to mimic that might help out a little.