Here in this post we present in the wonderful tutorial for the fake shadow. In the olden days of visualization, a technique has been very useful for this kind of situation; nowadays rendering time goes up dramatically. Let’s find out the how you can make the fake shadow by OPACITY MAPS.
You see the location of the opacity map in relation to the vray sun.
Elevation, here you will see the rotation of the opacity map. It should face flat to the direction of the sun to maximize coverage and lessen distortion of the cast shadow.
Another view showing the components
Add the opacity map to the opacity map slot and use use a vray material or a standard material for Opacity Map Settings.
How the setup is in another camera angle to breakdown scene.