4 Replies Latest reply on Jan 26, 2011 8:28 PM by Rick Gerard

    Rendering?  (beginner question)

    teho59 Level 1

      Hi,

       

      I am trying to learn myself AE and I tried a simple rendering. I have a canon 7D video clip, 1920x1080 23.976 fps. Filesize is 88.7MB. I don't do anything to the file, just creates a new composition. Changes output module to H.264 and start rendering. Now I get a file of about 6 MB with very bad quality.

      If I use output module quicktime with pgoto-jpeg I get a filesize of 3-400MB with ok quality.

       

      What I thought I could do is to take my videoclip, render it and get a file about the same size as the original with the same quality. Am I doing something  wrong or am I missing something.

       

      I use AE CS5.

       

      - Terje

        • 1. Re: Rendering?  (beginner question)
          Todd_Kopriva Level 8

          This FAQ entry should get you started in understanding compression options and tradeoffs:

          http://forums.adobe.com/thread/729526

           

          The most important question to ask yourself is what you intend to do with the output movie. If you're going to post it online for playback, the movie needs to be highly compressed; if you're going to use it as an intermediate file for further post-production work, the output movie needs to be losslessly compressed.

           

          The files that came off of your camera were in a somewhat compressed acquisition format. When you rendered and exported to H.264 from After Effects, you were using settings more appropriate for online distribution and playback.

          • 2. Re: Rendering?  (beginner question)
            teho59 Level 1

            Hi,

             

            Todd_Kopriva wrote:

             

            This FAQ entry should get you started in understanding compression options and tradeoffs:

            http://forums.adobe.com/thread/729526

             

            The most important question to ask yourself is what you intend to do with the output movie. If you're going to post it online for playback, the movie needs to be highly compressed; if you're going to use it as an intermediate file for further post-production work, the output movie needs to be losslessly compressed.

             

            The files that came off of your camera were in a somewhat compressed acquisition format. When you rendered and exported to H.264 from After Effects, you were using settings more appropriate for online distribution and playback.

            First of all, my intention was to create a file equal to my source like it was not touched. Nothing more.

             

            Thanks for the FAQ entry. As I understand it now the output from AE is more like to create a file for further processing in other applications or make a final product in Media Encoder, correct?  I created a file from AE at abount 350MB and added it into media encoder. It created a h.264 file about 63MB. It seems I kept most of the quality. I will investigate for on this. You put me onto the track.

             

            Thanks!!

             

            - Terje

            • 3. Re: Rendering?  (beginner question)
              teho59 Level 1

              teho59 wrote:

               

              You put me onto the track.

               

              The problem was the target bitrate, I used a bitrate of 3mb. The source (canon 7d) has 48mb.  When I also use 48mb the filesize is about the same as the source and the quality the same.

               

              - Terje

              • 4. Re: Rendering?  (beginner question)
                Rick Gerard Adobe Community Professional & MVP

                I couldn't recommend rendering anything other than a quick test render to H264 from the After Effects render cue. H264 is an output codec that needs multi pass rendering. It is not a production codec. The only time I use H264 directly from AE is for short previews that need to be sent to a client as a motion or concept check. Rendering to a lossless (animation codec) or a nearly lossless like photo jpg at 95% will go much faster than rendering to H264 and give you something you can use later in the production pipeline without huge losses due to compression artifacts.

                 

                Hope this helps. I can see that it's time to put together a recommended workflow tutorial.