4 Replies Latest reply on Mar 30, 2016 1:56 PM by Szalam

    Motion Blur and Mask feather render issues

    keith reinbold

      Hi All,

       

      I am seeing a little issue in with AE CC 2015 (13.7.0.124)

       

      When using larger frame sizes (4k) and using motion blur my render times go through the roof if I include a mask that has a feather on it.  A comp that might take my machine to render in 10 minutes with motion blur and no mask feather would not take about an hour.  I can have masks in the scene without an problem but if I even use say a 10 pixel feather the render times just skyrocket.  Just wondering if anyone else has scene this behavior and if anyone has a solution.  One thing that works is pre-comping the layer with the feather mask or rendering out a movie replace but those seem like just work-arounds.

       

      Machine

      Windows 7 pro

      i7-5960x 3.00 GHZ cpu

      Titan x video card

      64 gb of ram

       

       

       

      Keith

        • 1. Re: Motion Blur and Mask feather render issues
          Dave LaRonde Level 6

          Um, not really -- you're working with four times the number of pixels found in HD footage on each and every frame.   Since AE CC 2015 can't take advantage of all that RAM for multiprocessing, you're kind of stuck.  A workaround is to install AE CC 2014, which can read & open the newer version's project files, and use multiprocessing there.

           

          When I started using AE with version 3.1, running on a single-processor PowerMac OS 8.6, you would do the following for a 30-second, 640x480 29.97 spot at the end of the work day -- set up your AE render queue.  Do a project save. Hit the render button.  Go home.  Hope the render was done by the time you came back in the morning.

          • 2. Re: Motion Blur and Mask feather render issues
            keith reinbold Level 1

            Man that sucks.  I am seeing the same issue with an HD (1080x1920) project I am working on now and just never remembering mask feathering and motion blur when put together would increase render times.  I started with AE 4.1 and well remember all night rendered for a small SD projects.

             

            I am just comparing the render logs from pre mask feather and post on the same project but with motion blur turned on. It is almost and hour more so seems like something else is going on like the multiprocessing issue AE CC 2015 you brought up.

             

            thanks

            • 3. Re: Motion Blur and Mask feather render issues
              Rick Gerard Adobe Community Professional & MVP

              The entire rendering engine is being rebuilt and the AE team is working hard on improvements but there's a long way to go. Multi Processing, which was really render multiple frames simultaneously, will not be redone because it was horribly inefficient, incompatible with a ton of effects and codecs and generally a mess. The new system is supposed to more efficiently use system resources. Even when it does if you quadruple the number of pixels you are going to drastically increase render time. Them's just the facts.

               

              For me I just carefully pick and choose how and when I'm going to be using effects that take forever to render. Unfortunately there is no magic bullet. Efficient workflow and rendering just takes experience and planning.

              • 4. Re: Motion Blur and Mask feather render issues
                Szalam Adobe Community Professional & MVP

                Rick Gerard wrote:

                 

                Unfortunately there is no magic bullet.

                 

                Well, technically... Red Giant | Magic Bullet Suite

                 

                Rick Gerard wrote:

                 

                Multi Processing, which was really render multiple frames simultaneously, will not be redone because it was horribly inefficient, incompatible with a ton of effects and codecs and generally a mess.

                 

                It really was bad and in need of an overhaul! Working on a project with MIR? TOO BAD - no multi processing for you! Terribly frustrating.

                 

                Now, back to the issue at hand. Mask feathering is fine. Motion blur is fine. But put them together and it's disaster? I can't test this myself (my CC 2015 machine is miles away at the moment), but you say precomposing the feathered mask layer makes the speed go back up? That sounds like a bug to be reported! Feature Request/Bug Report Form