Hey, I am the guy who was miraculaously saved from having to replace an expensive nikon 300 2.8 AFS I lens by the presence of the 52mm rear drop in filter of my aforementioned lens. http://www.photo.net/nikon-camera-forum/00YIlx This has given me an idea since I like to shoot portraits with the 300- using a 52mm Zeiss softar inserted in the rear filter slot. Anybody tried this? Do you think it will work in terms of diffuse soft focus effect? Or will the picture look lumpy or have irregular patterns as the filter is the last before the film plane?