What size is the render? What settings?
Shadows in Sketch render take very long.
If you are going to overlay the sketch on top of another render in a photo editing program, that will have shadows already.
If you want to keep things colour-free (sort of), a quick white model cinerender render of the same shot will get you shadows a lot quicker.
If you have a very high polycount (for example a lot of trees / hedges with individual leaf materials), that might be a problem. Also consider that a lot of small leafs will just end up as a nearly massive mass of black lines, not the sort of thing to associate with a tree.
Bumping anti-alias to 4 also increases render times a lot, while not really looking all that much different from having it set at 2.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
Windows 10 Pro
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