Realistic oudoor Lighting with Light Tracer

1. The first thing to do is check the mesh of your objects. make sure that there are no jutting eges and that the mesh is clean. The easiest way to smooth out jutting edges is with the MeshSmooth modifier.
   
   
2. Now, under the Lights menu, select skylight.
   
   
3. Place the skylight far above the scene. From my experience, exactly where you place the skylight will not really effect your result, as long as the light is above your objects.
   
   
4. Now under the Render menu, under advanced lighting, choose the Light Tracer option. The Light Tracer is a wonderful tool that will increase the realism of your lighting effects. The only sacrifice you will make is a large increase in rendering time, but it all will come down to the complexity of your scene.
   
   
5. Now, render your scene. You will see the objects will look oddly bright, but there will be shaded segments where two faces intersect. You can see that the scene now has alot more depth, and feels more lifelike.

For some people this may be enough. Using these teqniques can produce good looking renders without too high an increase in render time. But of course, outdoor scenes usually have sunlight. The image you just made is great for simulating cloudy/overcast days. Read below to find out how to add sunlight to the previous scene:

1. under the Lights tab, select a direct light and face it at an angle onto your scene. Put it in the direction you would want the objects to cast shadows in.
   
   
2. Under the direct light's Modify tab, turn shadows on. Which type of shadow you choose is all up to you. Use area shadows for realistic shadow dispertion, ray traced shadows for harder edges, or expirement with some of the other types. Turn the power of the light up or down for brighter or softer sunlight.
   
   
3. Render your new scene and enjoy!