4 Replies Latest reply on Apr 5, 2009 4:42 PM by Adolfo Rozenfeld

    Keylight v. DV Matte Pro

    Top Branded Clothing
      I'm using Keylight with a green screen chromakey and MPEG files from my FX1 (not a great idea, I know).
      Is DV Matte Pro for After FX worth considering?
        • 1. Re: Keylight v. DV Matte Pro
          ChrisPoisson Level 1
          Keylight is a great tool and so is DVmattePro. More a question of how you like each interface. They both work great.
          • 2. Re: Keylight v. DV Matte Pro
            Adolfo Rozenfeld Adobe Employee
            Keylight is an extraordinary keying technology. In fact, it's used for very high end keying in VFX work all the time. But it works best when you feed it footage with adequate color sampling for keying. If not, it will pull a key perfectly... which for undersampled formats like DV or HDV could mean revealing ugly stair steps in the matte edges.

            DV Matte Pro, from what I saw, is very good at pulling a key while disguising the flaws of the 4:2:0 color sampling grid in those formats. So if you're trying to key DV or HDV footage, it can be an excellent product.

            Adolfo Rozenfeld - Adobe
            • 3. Re: Keylight v. DV Matte Pro
              Top Branded Clothing Level 1
              Thanks for the reply. The problem I have is with HDV and in particular, with getting a good solid black within the mask.
              I heard somewhere that DV Matte Pro works better with HDV so that was the reason for asking.
              So do you have any tips for working with Keylight and HDV to get better blacks?
              Or maybe I could try another and better recording format, such as XD CAM from a Sony EX1 (which would mean another camera!)?
              Or another idea, which I haven't fully got to terms with, is bypassing the HDV recording format from the FX1 and using the component output to capture via a suiable card in my PC.
              • 4. Re: Keylight v. DV Matte Pro
                Adolfo Rozenfeld Adobe Employee


                Your description of black not being "solid" in your key is not related to mattte edges (which could the weak link when keying HDV) and it's something that should be very easy to fix.

                You see, Keylight is working very hard to preserve semi-transparency in your matte, so that hair (not to mention smoke, etc) keys naturally. And because of that, Keylight is being conservative in considering parts of your subject as semi-transparent. That's a good thing.


                In Keylight, change the View menu from "Final Result" to "Screen Matte". This will give you a grayscale representation of the matte (ie, black areas represents full transparency, full white respresents completely opaque areas and grey areas, everything in between).

                Before anything, increase a little the Screen Gain parameter. See if this makes grey areas become closer to white. If you need to push the slider a lot, then it's a sign you have to do what I'll explain below. Don't push it.

                There's a section in Keylight called "Screen Matte". This has controls not unlike the principles of regular Levels. The "Clip black" parameter forces near-black areas to become fully black, and thus move pixels from semi-transparency to full tranparency. "Clip white" forces almost opaque areas to become fully opaque (which is what you probably need in, from your description).

                After doing this, set the View menu again to "Final Result" and see if it works better for you.


                For a video tutorial on keying with Keylight, go to the Adobe website at www.adobe.com/go/vid0229


                Adolfo Rozenfeld - Adobe