3 Replies Latest reply on Feb 10, 2012 7:59 AM by bogiesan

    After Effects key light Issue

    Bret_Richter

      I am following a tutorial to remove a color key for my blue screen.

       

      I am new to this, so I may not have all the terminology down.

       

      1. I choose a color key and remove the background.

      2. Then I create a garbage matte and expand it until there is a blueish halo around the subject.

      3. Then, I am supposed to be able to then use keylight to remove the halo, but when I use the eye dropper to select the halo, the subject goes away and it leaves a gray, choppy, "halo" around where the subject was and the subject is then gone.

       

      Any ideas? In the tutorial, the keylight perfectly removed any halo around the subject. What am I doing wrong?

       

      Thanks,

       

      Bret

        • 1. Re: After Effects key light Issue
          bogiesan Level 4

          Unfortunately, no, it's not that easy to pull a key but, umm, which tutorial are you watching?

           

          You can search the entire net for advanced Keylight assistance but have you opened the Keylight manual that came with AE? It is a very complicated filter. I think the inventors are British so the terminology is odd, too.

           

          Much of any chromakey's success is based on the quality and resolution of the video file. Every good key is a ocmplicated multilayerd affair, often requiring several copies of the footage, each precomposed and tweaked with additional pre-processing filters. Then Keylight is applied to precomp, not to the video file.

          • 2. Re: After Effects key light Issue
            Mylenium Most Valuable Participant

            You remove the fringes by using the Alpha and grey level rollback options. The color picker really only defines the base keying color and you mess that up.

             

            Mylenium

            • 3. Re: After Effects key light Issue
              bogiesan Level 4

              Mylenium wrote:

               

              You remove the fringes by using the Alpha and grey level rollback options. The color picker really only defines the base keying color and you mess that up.

               

              Mylenium

               

              You will need the manual to understand what Alpha and Gray Level Rollback are and what they do. Still, even with Keylight, it's difficult or impossible to pull a clean key with one layer with one applicaiton of the filter if you are using DV. What are you using?