I have the 49 mm lens adapter ring, but I don't have that many 39 mm filters and would just as soon use an adapter ring with it and use my Lee filters with it. I just wondered if there were any problems with vignetting? The lenses I would be using them on are the 35, 50 & 90 mm M lenses; I think 2 and/or 2.8 are their widest apertures.