When you first started out on your journey to becoming a videographer or filmmaker, you probably had some thoughts about how cool it would be to create awesome slow-motion videos.
Maybe you saw an inspiring slow-mo scene in one of your favorite movies (like The Matrix) or saw some incredible footage on Youtube from a camera slow-mo test.
But how do you create awesome slow-motion videos? Is it possible to create slow motion with every type of camera or only specific ones? And why is knowing how to create slow-motion video important?
This article aims to tell you everything there is to know about how to record awesome slow-motion video, as well as how to edit awesome slow-motion video, too.
From how to, to tips and tricks, to just plain good advice, here is everything you need to know to get started creating your own slow-motion video.
Let’s dive in!
What is Slow-Motion Video?
Slow-motion is a filmmaking technique in which the action in the frame is made to appear slower than it was recorded, usually by capturing film or video at a much faster speed than it will eventually be played.
This might sound counter-intuitive, but all slow motion is created by high-speed video. When I say high speed, what I’m really talking about is a higher frame rate.
What is Frame Rate and what does it Mean for Slow Motion?
Frame rate refers to the speed at which your camera captures frames. In order to understand slow motion and how to capture it, the first key is to understand frame rate and how it works.
That’s because the more frames you have per second, the slower you can play the footage back and keep it looking smooth.
For example, the typical frame rate is 24 frames per second, or 24 FPS, which is the standard “normal speed” for most theatrical films and video projects.
By capturing frames at a rate higher than 24 frames per second, your footage will appear as if it’s happening slower when you play the footage back at the normal 24 frames per second speed.
On old-school film cameras, capturing frames at a higher speed was made possible by over cranking the camera’s hand crank at a faster rate.
Overcranking is still used as a term today but refers to the process being done through the camera’s internal mechanism rather than using an actual crank.
What FPS should I use for slow motion?
There are multiple frame rates you can use to create slow-motion video. In truth, any frame rate above 24-30 FPS is useful for creating slow-motion videos, though they vary in look and feel.
Here’s a video from The Slanted Lens that does a good job explaining frame rates and slow-motion.
As a general rule, the higher the frame rate, the slower you can make your footage.
This doesn’t mean that slower is always better, however. It all depends on how slow you want your footage to look and how long you want the clip to go for.
Another rule: The higher the frame rate, the longer your slow motion shot can last.
What Frame Rate is best for Slow Motion?
Video footage captures at different frame rates when played back at 24 fps, looks different. Here’s a good video from B&H with some solid examples on how the various frame rates change the look and speed of your slow-motion video:
Starting at 1:15, you can see four different clips taken at four different frame rates side by side to get a sense of how each one looks and feels compared to the other.
Notice how the 60 fps shot is slowed down but is still relatively quick? And how the clip runs out faster than the 120 fps and 180 fps versions?
Meanwhile, the 120 and 180 fps clips are more like what we imagine as “slow motion” based on what we’re used to seeing in popular culture.
But as the video creators point out, the 180 fps version might be too slow and dragged out, whereas the 60 fps version, by comparison, is too quick – leaving 120 fps as the sweet spot for awesome slow-mo!
Can you do Slow-Motion with 30fps?
Technically, anything you shoot above 24 fps can be made slow-motion by playing it back at 24 fps – that is, if 24 fps is going to be the frame rate for your video or film.
The European television standard PAL traditionally requires the final film to be delivered in 25 fps, and the US standard NTSC uses 30 fps, meaning that you won’t get any slow-motion footage from recording in 30 fps if the delivery is also going to be in 30 fps.
That said if you’re aiming for 24 fps, shooting in 30 fps won’t actually slow the footage down very much unless you add an additional slowing effect in post, but we’ll get into that in the next article.
However, when you shoot at 30 fps, it creates a specific look that can be used for specific types of scenes.
Shooting at 30 fps or a similar range between 28 – 34 fps can be used to smoothen out movements that would otherwise come off as jerky at a normal 24 fps rate, or add an additional “drag” to the movements of characters in the frame to create the look and feel of a character wading through water.
Can you do Slow-Motion with 24fps?
Technically yes. It is possible to take video footage recorded at the average 24 fps frame rate and slow it down in post-production, but it can reduce the quality and create a type of stutter – all of which we’ll get into in a bit.
If you are planning ahead for a shot or sequence to be in slow motion, it’s better to shoot at a higher frame rate because you will have more frames to work with, which will make it look much smoother.
Is 60 fps enough for slow motion?
As you saw in the video above, 60 fps is definitely slow – just not what we typically think of as true “slow motion.” That said, you can still create quality slow-motion video clips from 60 fps footage by slowing it down to 24 fps.
If you want the footage to appear slower or the clip to last longer and still maintain its smooth appearance (meaning no stutter) then you can use a post-production effect, like the Optical Flow tool in Adobe Premiere.
This will “interpolate” new frames that fill in the gaps of what was shot but is only effective up to a point. But more on that in a bit.
Do DSLR have slow-motion capabilities?
As we’ve established, depending on the type of slow-motion you are trying to shoot, most DSLRs these days have slow motion capabilities. Depending on your DSLR, you should at least be able to shoot up to 60 fps at 1080p resolution.
Here’s a video from Think Media with some tips on shooting slow-motion footage with DSLRs and action-cams:
However, not all DSLRs can shoot slow motion at higher frame rates, making the best DSLR cameras for slow-motion those that can shoot are 120fps cameras.
What is a 120fps camera?
A camera is considered a “120fps camera” if they can shoot footage up to 120 fps at 1080p resolution, which you might remember as the ideal higher frame rate for shooting awesome and smooth slow-motion footage we mentioned above.
Some of the most popular high-end mirrorless and DSLR cameras are able to do this, which we will list below.
What about Shutter Speed?
Your camera’s shutter speed is the other important element to getting slow motion to look right.
Shutter speed refers to the length of time your shutter is open and exposing your camera’s sensor, or in the case of film cameras, the film itself, to light.
The longer your sensor or film is exposed to light, the more exposed the image will be, or in the case of high frame rate shooting, the more motion blur will appear on your footage.
Here’s an incredible video from The Slo Mo Guys that captures the shutter in a camera at 10.000 fps:
For smoother, less blurry footage, you need your shutter to be open for less time. But that also means the less time your shutter is open, the less light your camera will be exposed to as well.
This shutter speed issue is why some slow-motion shots in older movies have that “over-cranked”, blurry quality to them – and why your slow-motion footage could turn out the same way if you don’t change the shutter speed properly.
What Shutter Speed should I use for Slow-Motion shots?
The goal when capturing slow-motion footage is to create a natural amount of motion blur. Your shutter speed is set to be open for 1/50th of a second when shooting at the standard 24 frames per second.
That means, to recreate the most natural-looking motion blurs when shooting slow motion, always set your shutter speed to a rate that’s double that of your frame rate.
Following the double, or 180° rule, match your shutter speed to whatever frame rate you are shooting at.
You can learn more about shutter speeds and the 180° rule in our article How to Choose the Right Camera Settings for Video Production.
Depending on your camera, you may actually have the option for true 1/48th shutter speed, but certain cameras like DSLRs don’t give you as wide a range as cinema cameras do.
Here’s a quick ratio table as a shorthand to help you set your shutter speed at whichever frame rate you decide to shoot your slow-motion scene with:
- 24 fps = 1/48th or 1/50th shutter speed
- 30 fps = 1/60th shutter speed
- 60 fps = 1/120th shutter speed
- 120 fps = 1/240th shutter speed or 1/250th shutter speed.
- 180 fps = 1/360th shutter speed
Once you know what you’re doing, you can always make a creative choice to shoot at higher or lower speeds to create a specific effect.
For example, if you want a blurrier, over-cranked look to create a chaotic, visually disorienting moment, you can shoot your slow-motion scene at a lower speed.
Also, you might find yourself in low-light situations where you can’t shoot at such high shutter speeds. In that case, you’ll have to lower your shutter speed in order to get usable footage. It’s better to lower your shutter speed than get unusable noisy footage.
What about Lighting when Shooting at Higher Shutter Speeds?
In addition to changing the level of smoothness and crispness of your slow-motion footage, higher shutter speeds mean that your footage will need more light to be properly exposed.
This is because, when your camera’s shutter is open for less time, it is taking in less light. This means that the higher frame rate and shutter speed you shoot at, the more light you will need.
Let’s say you are shooting a daytime exterior in slow motion. Because you have the sun as a key source, you won’t be as affected by shooting at higher speeds and frame rates.
Actually, shooting at a higher frame rate/shutter speed may negate the need for an ND filter and make your footage look less exposed in a positive way.
The same is not true for shooting slow motion during a night exterior.
In actuality, you’re going to need a lot more light than you would have in a normal situation because less light will be getting through to your camera’s sensor.
One more thing: watch out for Light Flickering!
Another thing you will discover at higher frame rates is how certain light creates a flicker effect.
When you shoot a scene at a normal frame rate, these subtle changes in light are harder to pick up. But when you shoot at a higher frame rate, even subtle changes can make a big difference.
One example of this is when shooting slow-motion footage with tungsten units. Tungsten units have an alternating current, which rapidly heats and cool as they cycle.
When shooting at high shutter speeds, this cycling appears at a flicker in your footage.
Here’s a video from “I’m Jason Anthony” that talks about light flicker and slow-motion:
To avoid this, you can use 2K or higher units, as the size of their filaments don’t allow them to cycle and cool down in the same way. You can also use HMI or Fluorescent bulbs – as long as you pair them with electronic flicker-free ballasts.
LEDs are the wildcard – the higher end professional units these days are built not to flicker (flicker-free), but make sure you do your research on a particular unit before you rent or buy it specifically for a slow-motion/high frame rate shoot.
If you DO get flicker, here’s a short video on how to remove it (starting at 1:25):
How do I Record Slow-Motion Video?
To create a slow-motion effect, you need to change your camera’s settings to a higher frame rate. The main way is to change the frame rate and shutter speeds manually on your camera’s general menu.
If you don’t know how to do this already, you’ll need to look up whatever specific camera you have for the exact instructions.
Also, before you go out and rent or buy a camera, or plan your video shoot around a specific style of slow motion, you need to figure out if your camera is capable of shooting at the frame rate you are looking to create.
For example, in the past, most DSLRs used to cap out at 60 fps, while 120fps+ was reserved for higher-end cinema cameras.
But now, as technology is improving, more cameras can shoot at higher frame rates, and some, like the Panasonic GH5, use something known as a variable frame rate (or VFR) setting to shoot at frame rates above 60 fps.
What’s the Difference between VFR and other Slow-Motion Frame Rates?
VFR allows you to adjust the frame rate manually through the camera’s settings, and automatically play it back at a lower fps so you can see the slow motion in real-time.
This is not to be confused with the term variable frame rate as it pertains to compressing the video to different formats during playback.
With VFR on your camera, you don’t have to wait until post to see your high frame rate footage in slow motion – it actually converts the frame-rate on the camera itself, transforming the footage into slow motion then and there.
Keep in mind that shooting in VFR on most cameras doesn’t allow for capturing audio. So if you plan to shoot in 60fps, and want to capture audio, you need to shoot in normal 60 fps mode and not 60 fps in VFR mode.
This can be a bit confusing at first, so it would make a lot of sense if camera companies would only make VFR available for frame rates above 60 fps.
Shooting Slow-Motion with a Gimbal.
If you are a videographer shooting B-roll for a commercial project of any kind or shooting a narrative scene without dialogue that is intended to be a character introduction of some kind, consider shooting your slow-motion footage with a gimbal.
Using gimbals to shoot your footage already gives a magical or elevated feeling to your work. Watching footage that seemingly floats through the air around a subject is one of the coolest camera-tricks out there.
Applying a slow-motion effect to the footage you shoot with your gimbal can create incredible shots, and elevate an already beautiful or cool scene to feel even higher in production value.
Faces get more expressive. Actions are more defined. Moments just feel bigger.
For more about that, this video from Momentum Productions provides some great examples (and How-To’s) on the how and why of using slow motion with your gimbal:
Just watch the first two minutes to get a sense of what we’re talking about, and think about how you can use slow motion in combination with your own gimbal or steadicam rig to help you elevate your filmmaking and videography to create awesome slow motion!
If you’re interested in buying a gimbal for creating cool looking slow-motion footage have a look at our article Best Gimbal Stabilizers For DSLR And Mirrorless Cameras.
Editing your Slow-Motion Footage.
Once you capture your slow-motion footage, unless your camera has variable frame rate capabilities, you will need to convert your higher frame rate footage back to 24 fps in post-production.
The next step of our guide will be how to do that, as well as different tools you can use to create awesome slow-motion videos with editing!