Creating realistic sunlight shadows could be an important part of the rendering process for some Autocad 3D models, especially those in the architectural or urban planning context. We explore the various settings in our Autocad 3D training courses.
When the modeling process is complete we set the camera to a good view of the scene. Next we note the Sun & Location tab in the Rendering section of the Autocad 3D interface. Click the  Set Location button, then Use Map, and choose Australia and Sydney and Accept. Note that the y-axis represents the North direction by default, but it’s also possible to select the button in order to specify a North axis line of your own choice. Next turn on Sky: Sky Background & Illumination. And in the Sun Status section switch off the Default Lighting since this does not usually produce a good result.
Select Full Shadows and render the scene again. Note that if the render is too bright at this point you may type UN (for units) into the Command line, choose Lighting Units and either International or American. This is in order to create realistic photometric lighting.
The Generic Lighting is adequate for spotlights and point lights created via the Lights tab. Note that it’s possible to adjust the date and time of day. Change the time to morning or afternoon sunlight, which is best for interior shots. Renders are often taken for midwinter sunlight. Click on the small arrow for Render Settings; change the quality to Medium, and in Indirect Illumination turn Global on for bounced ambient light. It should take about one minute to render a simple scene. You may also Adjust Exposure in the Render tab drop-down arrow, and change to Mid-tone: 1.5, etc.
In order to create Solar Studies (also known as Sun Path Analysis) and animated sun paths, you would need to use a program like Autodesk’s Project Vasari, which is a BIM (building information modeling) program, or Autodesk’s Revit Architecture, AutoCAD Architecture, or Ecotect.
The 3d interface in Autocad is user-friendly and easy to learn, and we take time to teach a broad range of applications in our classes including modeling, materials, lighting and animation. See many examples of our clients’ work on our Facebook page. For more information there are lots of resources on the web, but try the Autodesk site to begin with: www.autodesk.com. Support options and user forums are also available from the home page.
Other related Autocad 3d Blog Posts:

• Autocad 3d introduction
• Autocad 3d modeling
• Autocad 3d blocks
• Autocad 3d commands
• Autocad 3d basics