I have been using the latest version of premiere pro and am very new to editing video. The product that I am editing is ceramic tiles. The issue that I am getting is that I am using green screen so upon using ultra key then using matte generation I am unable to find the correct mix of highlights and shadows etc for a good key. I have done a lot of videos for tiles and am happy with the results so far but am struggling with mostly anything black and especially if its shiny and black. I would really appreciate some advice on what I am doing wrong.