8 Replies Latest reply on Nov 14, 2011 8:35 AM by Paul R Stark

    PP CS5/5.5 chroma key better than AE CS4?

    Paul R Stark Level 1

      Hi everyone.

       

      I think I read somewhere a while back that the chroma key in PP CS5/5.5 is better than AE CS4's Keylight. In fact, the PP effect may be an improved Keylight , but I can't recall this for certain.

       

      Can anyone verify this?

       

      Thx.

       

      Paul

        • 1. Re: PP CS5/5.5 chroma key better than AE CS4?
          Colin Brougham Level 6

          Keylight is still far superior, but Ultra Key (the keying effect I'm sure you're talking about) is fairly capable and has the added benefit of being CUDA acclerated, so your keys play in realtime. It works best on clean, well-lit, well-shot footage.

           

          Keylight and Ultra are not related; Keylight is a third-party product from The Foundry, whereas Ultra is derived from Adobe's acquisition of Serious Magic and their chroma keying software.

          • 2. Re: PP CS5/5.5 chroma key better than AE CS4?
            Paul R Stark Level 1

            Thanks, Colin. That sounds like the answer I'm looking for.

             

            However, by "well lit", do you mean brightly or just evenly or both? Everything I've read says brightness is not as important as the green screen being evenly lit, but I'm not sure my experience bears this out.

             

            Thx.

             

            Paul

            • 3. Re: PP CS5/5.5 chroma key better than AE CS4?
              Colin Brougham Level 6

              Evenly-lit screens are important, but getting the right exposure on the screen is important as well. Depending on the camera you're using, you can end up with a lot of noise in the green channel, which can make keying a much more demanding exercise. That can be compensated for a bit by the exposure on the screen. Of course, that means you need to be concious of the lighting on your foreground subject, as well. Ultimately, keying is not just about putting someone or something in front of a green background and saying "go"--you need to experiment a bit with the setup and get a feel for the capabilities of your camera. It can be very time-consuming to rescue poorly shot chromakey footage...

               

              (But it can be done, if you're a masochist )

              • 4. Re: PP CS5/5.5 chroma key better than AE CS4?
                Paul R Stark Level 1

                Yes, I've been experimenting with it for two years using the Panasonic HVX-200p at 720p60fps.

                 

                In the end, after comparing the keys of a brightly lit background (which admittedly had some minor hotspots) to a lower and more evenly lit background (the foreground subject being lit the same), the results of the lower lit were superior with only a white balance, ND Filter off, Gain low and auto Iris capturing direct to Onlocation via firewire. It actually looks quite good with much less effort in AE.

                 

                Thx.

                • 5. Re: PP CS5/5.5 chroma key better than AE CS4?
                  Colin Brougham Level 6

                  I've keyed with the same camera for a couple of years now, and it's got a pretty narrow band in which greens are easily keyed. DVCPRO HD is not well-reputed for its handling of greens, or at least as a result of it's use with an older 1/3" sensor. I've gotten the best results with the exposure on the screen at about 50-60IRE, but that's just in my scenarios. Most of my material is recorded to P2 cards (though I did one long shoot with OnLo and a green screen), but the footage encoding is the same--it's all DVCPRO HD. I've got some stuff that I did recently that keyed like buttah with Ultra--I literally had a solid key in 20 seconds with just picking the background color and tweaking a couple parameters.

                   

                  So, since "brightly lit" and "lower lit" are subjective terms, it's hard to give you any specific recommendations other than to try to stick in a particular exposure range. All I know is that when your green screen footage is evenly lit and at mid-range exposure, Ultra does a pretty good job with minimal effort.

                  • 6. Re: PP CS5/5.5 chroma key better than AE CS4?
                    Harm Millaard Level 7

                    In addition to Colins remarks, a general rule is that the brighter the green screen background is shot, the more 'spill' you have and the more cleaning up needs to be done.

                    1 person found this helpful
                    • 7. Re: PP CS5/5.5 chroma key better than AE CS4?
                      Paul R Stark Level 1

                      Thanks, Colin.

                       

                      I'll be sticking with AE's Keylight since it is superior.

                       

                      Also, I have to get another camera (the Panasonic was on loan) and I'm considering the Canon XF100, but that also has a 1/3 sensor. Does that mean my greens will not be any better?

                       

                      Thx again.

                       

                      Paul

                      • 8. Re: PP CS5/5.5 chroma key better than AE CS4?
                        Paul R Stark Level 1

                        That's it! Precisely! That completely slipped my mnd. Hence my better results with lower light.

                         

                        Thanks a million.