6 Replies Latest reply: Feb 4, 2014 10:08 PM by Brendan.JB RSS

    Unusual render times


      Hello, I seem to be experiencing weird, fluctuating render times with my projects. Some 10+ minute projects render in 20 minutes or so, others like the one below take far too long for what they are.


      I am running a Macbook Pro, 2.5ghz Intel Core i7, 8GB 1333 Mhz DDR3 ram, and an AMD Radeon HD 6770M 1GB.


      Here is a current project I am working on at the moment - please excuse the blurred sections, this is an internal business video and I am required to do this for security.


      The maximum filesize will only be est. 134mb, the length of the video is 3 and a half minutes, and I am only rendering at 720p with 90 second keyframes. When I render this file it takes upwards of 2 hours; sometimes longer.




      The source files are 1920x1080 and 1440x1080, and I have 4-5 nested sequences approx 10-20 seconds long each with warp stabilizer applied to them.

      I also have fast color corrector applied to all clips. I usually have a VBR of min-4 max-6 but attempted to change it to CBR to see if that decreased rendering time; it didn't.

      I've also tried optimizing the memory for both rendering and memory in the preferences window, but I see no difference.


      Can you spot anything that might be causing this render to take so long?


      Thanks in advance for your help.




        • 1. Re: Unusual render times
          shooternz Community Member

          I am not surprised!


          You got a ot going on there in the differences between source and export


          Frame rate : PAL to NTSC...


          Square pixel to rectangular


          Dimension change


          WHy did you choose those settings?


          Did source footage match the project settings?

          • 2. Re: Unusual render times
            Brendan.JB Community Member

            Thanks for the speedy reply, shootemz. I had no control over the source footage unfortunately and the video needs to be uploaded to a private Youtube channel, so I just selected the Youtube preset from the Export Settings section - and Youtube seems to have a sad every time I try to upload anything that isn't 29.97fps so that's the one I chose.


            So all of the things you mentioned increase the encoding time? I didn't know that! I am new to this type of export. It's always been very straight forward in my past jobs. I guess I will play around with the settings and see if I can keep them as close to the source as possible. Thanks for the reply! If anyone else has any other suggestions I would love to hear them also.

            • 3. Re: Unusual render times
              shooternz Community Member

              Sounds like random settings choice issue!




              what are the source files?

              what was the sequence setting?

              • 4. Re: Unusual render times
                Brendan.JB Community Member

                Thanks very much for taking the time to help! It's very appreciated!


                There are 2 sets of source videos:

                Canon T2i: 1920x1080 @ 23.976fps

                Canon HD CMOS: 1440x1080 @ 25fps


                And one source audio file:

                Zoom H1: 44100 Hz 24-bit Stereo


                Sequence settings:



                Square Pixels

                Progressive Scan

                48000 Hz

                • 5. Re: Unusual render times
                  shooternz Community Member



                  You still got a lot going on there with mixed media, fx, warp stab. etc...but I cant see anyway around it in your case.



                  • 6. Re: Unusual render times
                    Brendan.JB Community Member

                    That's alright, cheers for the help!


                    At least now I know I should create some guidelines for clients for recording footage.

                    Much appreciated!