Hello,

Do you know how to blur the edges of a shadow?

How do you want to blur shadows?

The most physically correct way would be to create an area light instead of a point light, and increase the size of the light.

Another option is to use the old school depth map based shadows, and blur them using the texture blur controls.

http://www.sidefx.com/docs/houdini/render/lights [www.sidefx.com]
http://www.sidefx.com/docs/houdini14.0/render/shadows [www.sidefx.com]

I would like to make a shadow which are the other cars on the left and on the right of the mercedes.

egygabor
I would like to make a shadow which are the other cars on the left and on the right of the mercedes.

Remove the key light entirely, and only use an environment light. Your reference image has no direct light, only sky light.