Quote - ... Poser DOF is done (I think - not sure) by rendering the image from multiple camera positions and then blending (averaging) them together. So if you want really good DOF, you use a lot of samples. ...

....

In my subjective opinion, poser does not do that. The reasons for this can be seen in your image itself:

• the specular highlight and the reflection on the blue ball are relatively sharp, but if the camera would move they should be blurred as much as the specular on the far ball. If you would use a real camera to photograph the clouds, you would focus on the clouds, even if you photograph the clouds through a mirror that is only some inches away - specular highlights are just reflections of light-sources.

• try to use depth of field through a window (ie refraction node). It should work with a jiggle-camera.

I rather think firefly is using some trickery with the z-buffer to realize the depth-of-field, of course a am not sure either.