Samhain with say, a realistic sky atmosphere you can change the strength of the sunlight (general Tab) In Effects you can sellect shadow softness or go to the Shadow Buffer. And in Rendering you can have Shadow Accuracy and the other global Illumination decissions. And then you can add other lights either distant or specific, all modifiable in a variety of ways. Work on/modify the variety of lighting scenes in the browser to see how the effects were attained and the effects of modifications. And read the manual relating to light! Hope you find something helpful in all that

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