Hello, Some High res HRDI maps provide a "full-world" view, i mean sky + ground. But how can you simulate an object to be placed on the ground ? If i insert an object in any of my HRDI maps, the objects seems to float in the air, even with the fake shadow projection method.... Any idea ?? thanks :-)

It may be a problem like the Poser cove or shell backdrop, or the Daz Studio environment. You can't get shadows unless there is a backdrop object on which you have mapped your HDRI image. To be honest, when we see HDRI renders here, the camera angle is adjusted so there's no ground in the view, and there's always a table or other prop between the shadow-casting object and the ground.

You use shadow catchers-- the catch is, in C2 at least, and I think in C3 too, shadow catching doesn't work with anything but standard light sources (spot, bulb...). You create a rough approximation of the environment in 3d, on the properties tab, switch 'shadow catcher' on for every object that simulates a surface, and set the textures on the objects to be black with no highlight-- else the shadows will look odd. You can get a pretty nice composite with it, but as I said, I don't think it will work with the HDRI lighting. The image shows a composite I did entirely in Carrara, which turned out decent-- a wire frame of the scene, the background image, and the result.

EMC

Wow ! Nice ! Thanks ! But how did u create that soft shadow ? When i try to achieve such an effect with the shadow catcher, the shadow produced is always opaque, even with the spot light effect "enable soft shadow" turned on ?? Thanks !

BTw i fanally found that i just need to play with the shadow intensity param to achieve to good transparency of the shadows.... so no more question !! thanks all for helping me :-) Pete