Beware of Picnik, the accomplice to Flickr that can absolutely ruin images, AND re-post them willy-nilly, adding confusion ad-naseum.
I am reviewing my options for how to get pictures up and not have them bedevilled in the couldron of Picnik.
That B&W photo appearing earlier in this thread — though undeniably quite a striking scene — has probably been sharpened several times, and—? If so, it is a false representation of the nature of pinhole. We must all remember to show pinhole images for what they are, and leave their inherent failings alone. We've all got access to cameras that produce images of outstanding sharpness and beauty. Pinhole has a beauty all of its own and that's what we need to embrace, not summarily impose elaborate technical refinements. Enjoy it.