Can anyone tell me how depth of field works? The dialog I see when I pull up DOF does not match the C4 manual. Any ideas?

Ehm, wich is the problem exactly? If you are at this point the only thing you need is to hit the render button. But, maybe you have a more detailed question... Let me know, -TOXE

 

Hit the render button. A preview of the current settings of depth of field with render. Click the auto-update so you can adjust the settings. Click the little button that looks like a plus sign. And then use it to specific in the preview what object you want the camera to focus on. Then decide what speed you need to render at, as the raytraced depth of field can be slow depending upon your scene. Brian

OK. Take a look at the manual for starters. This dialog does not even match. I figured out how to use the "x" to set the focus point, but what do I set to tell how much of the image is in focus? The focus value changes with the positioning of the "x", and the DOF window in the manual does not have a "lens size" slider on it. What does it do?

The best way to see this is try and error. Check the "Auto Update" lightbox and Render. Play with the Lens Size slider to see how it works.