Instead of trying to find a $400.00 center filter for the 65mm Super-Angulon, does anyone have a tried and true work flow to minimize the vignette issue with this lens in Photoshop? I have worked some on this, but it seems like it might be a combination of overexposure of the neg to compensate for the dark edges and a vignette controls in Photoshop. I would like to have anyone else's experience with this issue. Thanks!