This is a must have item in your camera bag and for a fraction of the cost of other brands of Variable ND filters.So far I have tested it with several lenses and 3 different cameras using step down rings in low light and bright mid day light from the lowers ND2 all the way up to DN32 and so far have not seen any X pattern. A huge issue with many a variable ND filter, even with the really expensive ones.Color cast is insignificant too, but like ALL lower end ND filters there will be a color cast, hell even a $500 one will have some kind of color cast, again at a fraction of the cost to have a barely noticeable color cast, or at least one that can't be easily corrected in LRThe only real issue with this is if you are using the filter with the same thread size as your lens the vignetting is a little bad at both extremes, unless you zoom in with your lens. SO I bought the 77mm one for my old Canon 24-105 that has a 77mm thread on a full framed camera, and at the extremes of the ND filter and when my lens is at it's wider focal lengths the vignette is somewhat an issue, again a vignette is still easier to work with than the dreaded X pattern.Now adays I am shooting with Sony mirrorless and every lens I shoot with on my full framed camera is less than 77mm threading and the vignetting is no longer an issue at any range of the filter and at any focal length of the lens and I have been shooting the dang thing A LOT with my Sony.Crop sensor cameras should not have the vignetting issues with this filter.Above are some of the photos I have taken with the filter including my Canon 5D series and my Sony A7R series. The first 3 are of my Canon and the second 3 are my Sony