I didn't understand much of this paper. I'm looking forward to hearing about ICA, as I've never studied it but always have wanted to. I hope that Andrew can explain the difference between independent and uncorrelated and all those terms that seem like they should mean the same thing, but don't. I also don't know much about optics, so I think the main contribution of the paper is lost to me. Specifically, I couldn't really separate the contributions of this paper from the previous work mentioned. These questions are so general that I don't expect them to be addressed in the discussion board.