The soft shadows on a cloudy day are nothing more as Ambient Occlusion , how lower the GI so higher the AO..
Nice info Alex, thanks ...it is exactly how we should working in poser, make the base GI and control the sun and shadows .. the most reality to that ad the HDR IBL cloudy day that light up all the places where the sun light have not access.. and make the shadows nice and soft..
I do my photography now only in HDRI format so I have always perfect balance of the light and colors..however you can make syntetic HDR IBL Light probe maps, but for that I will have to make a video tutorial so you can follow the screen exactly, it is simple but much to do... you cant just put photoshop graphic and convert it.. but about that later... Have a great weekend everyone..

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