Strange outline after composite -- and it doesn't seem to be the typical problem

Heres a render using nodes for all sorts of things, including DOF… if you need it I can post the node setup. Does anybody know why the strange outline of the main ‘character’ is there? By the way, the outline only occurs after the composite is finished.
Any help would be greatly appreciated.


alpha’s are multiplied to zero. see wiki regarding pre-multiply alpha on the Alpha Over node.

Ah, but I have no alpha over node. :s
Edit: this may be useful: node setup:


You’re blurring the Zdepth set…and then mixing it back with the same image. dangerously mixing your metaphors. Then you’re Subtracting out a little blue, but where they match, you get white, which is the outline you see. To do DOF, I suggest you see http://mediawiki.blender.org/index.php/Manual/Depth_Of_Field

I also frequently hook in Viewers after every node just about, and set my UV window to see the Viewer, to check my work in progress.

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Thanks for the replies; that explains a lot about nodes that I didn’t know:) . I’ll keep playing around with this and see if I can fix the problem.