What 4x4 ND filters are recommended? (especially any more affordable ones!) Also interested in graduated ND 4x4 filters, and polariser 4x4 filters. I know the cheaper ND filters often have issues, but I'm hopeful there are some options out there which can give at least "acceptable" results relevant to the no budget indie level. I'll be using this on a Fotga DP3000 M3 matte box with Rokinon DS lenses and a Sony F3. These are the possible ones I'm looking at for now (open of course to other suggestions): http://www.ebay.com/itm/100x100mm-Neutral-Density-ND2-ND4-ND8-Gradual-ND2-ND4-ND8-filter-Kit-matte-box-/191191576133 http://www.ebay.com/itm/FOTGA-4-X4-Neutral-Density-Full-ND-ND2-ND4-ND8-filter-kit-for-Matte-box-Holder-/261153861690 http://www.ebay.com/itm/XCsource-4-x4-100MM-Neutral-Density-ND-ND2-ND4-ND8-Filter-For-Matte-Box-LF350-/310953307707 http://www.ebay.com/itm/FOTGA-4-X4-Neutral-Density-Gradual-ND-ND4-filter-for-Matte-box-Holder-FF-system-/261153856545 http://www.personal-view.com/deals/filters/other-filters-holders