Have you ever worked with drop-in filters, the ones that go behind the lens? The Sigma 15-30 is sharp, contrasty, renders beautiful color ... great lens on most counts, except that it doesn't take normal screw in filters. There's an adapter that lets it, but you put that on top of the petal hood, blocking the cutouts, and wind up with massive vignetting. Well, I'm definitely trying! Good to know people like to see purdy nature scenes, though, that gives me a little bit of push to go hiking with my camera...
no, never worked with those types of filters! hate the massive vignetting!! always nice to get a push