3 Replies Latest reply on Nov 23, 2012 7:17 AM by Dave LaRonde

    Decent slow motion without artifacts?

    nullsebasvideo Level 1

      I can't get decent half speed slow motion in AE CS6. Frame blending looks horrible with all the double contours in fast moving objects, and pixels motion looks much better motion wise, but introduces horrible motion artifacts. I also tried Pixel Motion using the Timewarp effect to have more control over tweaking it, but no matter what parameters I change, I still get the artifacts. So it looks like After Effects by itself doesn't have a good way to do slow motion that looks great, at least not for the footage I'm using.

      Are there any other filters I can try, whether in AE or 3rd party that will go a great job?



        • 1. Re: Decent slow motion without artifacts?
          Rick Gerard Adobe Community Professional & MVP

          Good slow motion depends entirely on your footage. If the original footage is 24P then good slow motion is more difficult. If the original footage is interlaced at 29.97 fps then good half speed is very easy to do and looks great. Highly compressed footage is even more difficult to get slow motion especially if you haven't transcoded it first to a production codec. You didn't tell us anything about your footage so I don't know where to point you.


          As for 3rd party solutions Twixtor is extremely good, but the same thing I said above holds true. If the footage is highly compressed and is at a low frame rate then good slow motion is very hard to do.

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          • 2. Re: Decent slow motion without artifacts?
            Mylenium Most Valuable Participant

            As Rick said, blaming it on a specific plug-in/ feature is kinda missing the point. Half the magic happens during shooting. If I knew I'd want to slow things down, I'd get the camera that would offer the highest framerate and least compression, even if it means an expensive rental of an ARRI camera. If that's not possible then you'll have to make do with what you have and try to fix it in post. Using a sophisticated tool like Twixtor no doubt is always an option, but many times it starts with simpler things like trying to reduce block artifacts or evening out color. Such basic stuff often helps the algorithms a lot. The same as you would when doing keying. Also you can always try to mask specific parts and slow them down in separate pre-comps. It may give alignment issues, but if you want to do some sky replacment or keying, it would be acceptable to proceed this way...



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            • 3. Re: Decent slow motion without artifacts?
              Dave LaRonde Level 6

              Please let me concur with the other two gents, who really know their stuff.  In Days Of Yore, slo-mo was accomplished by shooting at a high frame rate, then playing the shot back at the normal, slower frame rate.


              It still works:  if you shoot at 60p, conform the footage to 24p, and place it in a 24p comp, the shot's motion will be 2.5 times slower than normal.  It's still the best way to do it.


              Since we know NOTHING about the frame rate of your original footage nor how slow the motion should be, we can't really give you a straight answer.


              But we CAN tell you the truth: you can't shoot at any frame rate you want, take the shot to AE and expect magic to happen.

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