HDRI lighting can create great-looking renders but it often generates undesirably soft edges on shadows. In this four-minute video tutorial, recorded exclusively for CG Channel, visualisation artist Matt Guetta explains how to preserve crisper shadows in your V-Ray renders through use of the irradiance map.
Update: the video takes a while to start after the pre-roll ad. Leave it playing for 15 seconds and it should be fine.
Get the HDRI used in the video here (commercial link)