A discussion of lenses and optics, and how they affect depth of field behavior in an image.

We talk about depth channels, what they are and how they work. How depth of field can be simulated in Nuke with the ZDefocus tool. We also demonstrate the OpticalZDefocus gizmo, which is a tool for generating physically accurate depth of field. It does this using the depth of field equation, given lens characteristics and a focus distance.

You can set your lens and film-back characteristics, set your focus distance, and adjust the size of your bokeh with the aperture f/stop size, just like a real lens.

Some recommended links:
https://en.wikipedia.org/wiki/Depth_o...
http://www.photopills.com/articles/ul...
http://www.nukepedia.com/gizmos/filte...
http://www.nukepedia.com/gizmos/3d/do...