Ben Simonds shares a wealth of knowledge on achieving realistic depth of field effects in Blender in this tutorial. He points out common pitfalls and explains how to avoid them. A must read for every aspiring Blender artist!
Depth of Field can be a beautiful effect, adding both aesthetic interest to an image, and serving a narrative purpose in drawing the viewer’s attention to the centre of attention. But getting DoF right using Blenders compositing nodes can be tricky, as there are a few things to know about how the defocus node works, and some limitations it has that you need to know about. This post documents my own investigations, and hopefully should be useful for those new to the topic. It also touches on a few things that I haven’t worked out how to fix yet, so if there’s anyone out there with input I’d love to know your opinions.