I'm looking to achieve a certain effect in camera filtration. This particular piece that uses it well (although a bit heavily):
I've used pieces of optical glass to get the distortion effect in a corner or half of the frame, but I'm wondering what options I have to create the effect around the entire frame (vignette).
The obvious answer is to use a UV filter with various amounts of smeared vaseline and either hold it in front of the lens, or place it in a matte box tray that can be rotated. Are there any other techniques or glass objects you have found work well?