May 24, 2017

Watch: How to Get the Best Results When Faking Slow Motion in Premiere Pro

This is how to get your slow mo shots to look buttery and smooth without shooting at high frame rates.

Today's cameras, even the ones in smartphones, are capable of recording high frame rates at pretty decent resolutions (at least 720p). What does this mean? Slow motion for pretty much everyone! However, a lot of entry level cameras only get as high as 60 fps, which is definitely slow(er) motion than the standard 24 fps and 30 fps, but it certainly doesn't produce that real buttery smooth, honey-like slow mo you typically see in today's videos.

So, how do those of us who don't have a camera that shoots at 120 fps or more achieve these stylish shots? Well in this tutorial, filmmaker Peter McKinnon shows you how to do it by using features in Adobe Premiere Pro. Check it out:

Just to be clear, probably the best way to get good looking slow motion footage is to shoot with a camera that is capable of higher frame rates. You take out a lot of the limitations that way. 

However, if you don't have access to such a camera, you can fake it in post, though you will have to address those limitations I just mentioned, like avoiding shooting in front of a busy background. This is due to the fact that Premiere Pro's optical flow function can't really determine where the focal point of your composition is, so it kind of works its magic on everything within the frame and that, my friends, does not look too hot.

So, if you want to include some slow motion shots in your next video, make sure to plan ahead. Figure out which shots you want to slow down, shoot them under the conditions that won't make Premiere go cuckoo bananas, and then enjoy you're sweet fake slow mo shot. Keep in mind that Murphy's Law is a real thing, so make sure to do some tests and make sure it works before you make your slow mo shot the pièce de résistance of your project.      

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9 Comments

I have a better method (although more time intensive) that is based on the old system called step printing (Roger Christian's The Black Knight). Remember the battle scene in Star Wars six between Luke and Darth Vader? The method, step printing, is taking stills of each frame and repeating them. It does away with the artifacting and gives you a non-jittery slo-mo that almost has an etherial quality to it. I've used it with 5 and 6 repeats per frame with great results. Like I said, it's time intensive, but the result is so worth it, especially if you don't have high-speed footage to work with.

May 24, 2017 at 11:40PM

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Ronn Hague
Film Production instructor
1

That is essentially what the editing software is doing when you adjust the speed of a video to 50%. Each frame is essentially repeated once, as described in the video. Instead of frames playing in their normal sequence (1, 2, 3) they play as (1, 1, 2, 2, 3, 3).

"Non-jittery" is subjective, but while step printing or its digital equivalent don't introduce artifacts, I still think it looks jittery. It's effectively playing a slower framerate, so by definition the motion won't be as smooth. That's great for dreamlike effect, but it's not quite the smooth slow motion solution people would usually want.

I think the step-printing like effect of essentially playing 24fps back at 12fps is just fine if all you have is a 24fps camera. Optical Flow or other interpolation also has its limitations, but can achieve decent results sometimes.

The best thing to do is not work outside of your limitations. If you have a slow motion shot in mind, and you can't record in higher framerates, and interpolating between frames in After Effects or Premiere doesn't look good, then don't use it. Find another way to tell the story. If smooth slow motion is a crucial plot element to your film, maybe wait to make that film until you have access to the tools necessary.

May 25, 2017 at 9:10PM

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Christian Druitt
Director/Cinematographer/Composer
143

Great. But, twixtor is much better I guess.
Expecting a better tutorial on twixtor.

May 25, 2017 at 3:29AM

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Sameir Ali
Director of Photography
693

Another tip for getting better faked slow motion: shoot with your shutter speed twice the **target** frame rate, **not** twice the actual frame rate. This will cause the motion blur to look correct when played back at the desired speed. It is also easier for the software to determine what to interpolate.

May 25, 2017 at 10:14AM

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Joseph Moore
Director
224

So, for instance, if I plan to playback at 24fps a shot I filmed at 120fps I should try to shoot with my shutter speed at a 240th/sec to get a correct looking blur?

Is that what you mean?

May 25, 2017 at 11:35AM

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I have a Panny AGAC 160a that can over/undercrank, but its max frame rate is 60 fps. If I overcrank a shot, then slow it down further in AE or Premiere, do you think it will look more like it was shot at a rate higher than 60? Maybe even 80 or 120 fps?
Thank you in advance, Jeff!

May 28, 2017 at 10:31AM, Edited May 28, 10:31AM

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Wow. Ten minutes of that twitchy millennial to basically say "use optical flow".

Slow. Clap.

May 29, 2017 at 10:27AM

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Nice vid. Some more advanced tips:

If you are planning slow motion on a conventional camera, shoot at the highest frame rate possible, with the highest shutter speed possible. 30fps with a high shutter-speed will eliminate motion blur. Motion blur will definitely screw with the optical flow algorithm, and you can always add motion blur back if you need it to look more "cinematic"

Stabilize your footage first if its not. Again, any unwanted movement will cause strain on the algorithm.

Use evenly divisible numbers when slowing down your footage. This one comes from a friend that works at Adobe, and made sense when he told me - basically the algorithm is using "anchor" frames to base the new frames on, and if it has an even number of frames between the two anchors you increase the possibility of a good slow down.

Again, great job... I too love slow motion ... just shot 4 spots for a motorcycle shop in Brooklyn sledge-hammering helmets and igniting jackets... but this was shot on the FS700 at 240 fps... cant beat the real thing;)

https://vimeo.com/219576240

May 31, 2017 at 12:30PM

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Roberto Serrini
Director • Editor
268

i'm leanrning make video ... but it certainly doesn't produce that real buttery smooth, honey-like slow mo you typically see in today's videos.... http://www.hondaotolongbien.org/

September 14, 2017 at 3:55AM

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fordtranhung789
SEO intern
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