Special Offer

Select colour
Please add quantity{0} in stock

Special Offer

Added to your basket

  • Sub-total:incl. VAT

Sorry, an unexpected error has occurred. Please close this window and try again.

Select colour
Panasonic Online Price: Shop Buy direct from Panasonic Where to Buy Out of Stock at Panasonic Online In stock /content/dam/Panasonic/EC-icon/icn-stock-in.png In stock Out of stock /content/dam/Panasonic/EC-icon/icn-stock-out.png Out of stock Coming soon /content/dam/Panasonic/EC-icon/icn-stock-soon.png Coming soon Panasonic true false Please accept our Cookie Policy to add to basket Please accept our Cookie Policy to add to basket Visit Panasonic Direct Online Shop Photo of {0}

How to create slow motion video with Lumix cameras

How to create slow motion video with Lumix cameras

Lumix cameras have some of the best features for helping film makers create slow motion video. Damien Demolder explains the relationship between frame rates in-camera and on your timeline.

How to create slow motion video with Lumix cameras

We see a lot of slow motion video on TV, in the cinema and in online films because showing the world slowed-down not only helps to reveal the details of how high-speed events take place, but it can also support the creation of atmosphere while injecting a little more drama into every day occurrences. In wildlife documentaries slow motion footage allows us to see every detail as the lizard’s tongue lashes out for the fly, but in real-time it all happens in such a flash we’re as oblivious as the fly about what’s happening. And, with a romantic backing track, the waves breaking gently on the shore as the happy couple stroll along the sunset beach transport us, and them, to another dimension.
Slow motion video is, in its simplest form, just video footage shown at a slower rate than it was recorded. This stretches time, making things take longer to happen on the screen than they did in real life. If you just slow down regular footage however your final video will be a jerky and unattractive, so we need to find a way to achieve that slow motion effect but with beautifully smooth-looking movement that looks effortlessly natural.

The Principles

Most video is recorded at 24fps, 25fps or 30 frames per second. For each second of action the camera records 24, 25 or 30 frames video. Long ago it was agreed that this many frames in every second of footage were required to make motion in a film appear natural on-screen. The exact frame rate you choose will depend on where you will show your film; 24fps for cinema, 25fps for TV in PAL regions or 30fps for TV in NTSC regions – though any of those will look fine on the Internet. As we are in the UK, and our region uses the PAL standard, I’ll take 25fps as my base for examples in this piece, but it isn’t hard to convert that to 24fps or 30fps.
If you record a 5-second clip at 25fps and play it back at 25fps it will last 5 seconds and any motion in the scene will look normal. If you play that same footage back at 50fps the clip will only play for 2.5 seconds and the motion will occur at twice the speed it did in real life – everything will be sped-up. If you play it back at 12.5fps the clip will last 10 seconds and the motion will be slowed down to half the speed of real life. The maths are pretty simple – 25/12.5=2, so with this scenario we’ll have 2x slow motion.

The problem with this situation is that footage played at 12.5fps will look jumpy because it doesn’t have the enough pictures to display in each second to create motion that looks smooth to our eyes. Footage played at 12.5fps might look like an old Charlie Chaplin film or a flip-book. To achieve smooth motion we still need to play our footage back at 25fps, so to get a slow motion effect we need to record at a higher frame rate in-camera so we can slow it down afterwards. To get successful 2x slow motion that plays smoothly we need to set the camera to record at 50fps.
The key to whether we can create slow motion video that looks good is to find a camera that will allow us to record at these higher frame rates.
Fortunately the Lumix series offers users a very good choice of cameras that can record high-frame-rate video of the sort that’s ideal for playing back at lower rates for fabulous-looking slow motion. All of the current Lumix G and S series cameras, and many older models, allow us to create at least 2x slow motion through their 48, 50 or 60fps recording settings.

High and variable frame rates

High and variable frame rates

This is the list of codecs in the Lumix GH6, with the C4K 120p mode highlighted. With this option selected the camera will record 120 frames per second, which is many more than needed for ‘normal’ 25fps playback. With all those extra frames-per-second though, fast action will look very smooth when the footage is played back at 120fps. As this mode in is the regular list of codec options, and it allows audio and autofocusing, it is considered High Frame Rate video

Some Lumix models offer two approaches to recording at high frame rates – HFR and VFR options. HFR (High Frame Rate) are codecs with higher than usual frame-per-second recording rates which also allow recordings with audio and autofocus. VFR (Variable Frame Rate) modes don’t allow audio or AF, but they do allow a wider range of incremental recording frame rates, including frame rates that create fast motion. VFR also allows higher recording frame rates than HFR, so ultimately it can produce footage with a more dramatic effect.

How to create slow motion video with Lumix cameras

Not all codecs offer Variable Frame Rate shooting, but when one does you’ll see ‘VFR available’ in the on-screen display. You then need to go back to main menu page to the Variable Frame Rate option and switch it on

Using the HFR mode is really a short cut for slow motion as it only involves choosing a codec with a higher recording rate than you will use in your final film – which is simple to do in the camera menu. Once the footage is slowed-down though the audio will be unusable, so you either need to delete it or detach it from the video file before you slow the clip so you can use it separately. Having autofocus can be very useful, which is another reason some users choose HFR options.
Really though HFR codecs are designed to be played back at their recording frame rates to create extra-smooth motion in the final picture, especially when that motion is rapid. There’s no reason not to also use them for slow motion effects.

How to create slow motion video with Lumix cameras

This is the Variable Frame Rate control panel. You’ll see whether the option is switched on or not, and you’ll also see the details of the options you have selected and the effect they will have on your footage. Here a 240fps frame rate will play back at 10% of the original speed – so with a 10x slow motion effect

A HFR mode might be a codec such as 4K 50p that you intend to play back at 25p for a 2x slow motion effect. When you pick a codec that allows VFR you select the playback frame rate with the codec – such as 4K 25p – and then use the VFR menu to determine the final recording fps setting and to see the slow/motion effect expressed as a percentage in the display. When you play VFR footage back in the camera you get to see the effect immediately, as you do in your video editing software. HFR video needs to be manually slowed in post-production to see the effect otherwise it plays at the normal speed.

Creating slow-motion in post-production

How you deal with your clips as they are dropped onto your timeline depends on how they were recorded.

HFR:

You need to set the frame rate of your project as normal, which might be, for example, 25fps. Often when the first clip of a project is dragged to the timeline the editing application will ask if you want it to adjust the frame rate of the timeline to match the frame rate of the footage being imported. Usually this is a handy reminder and we allow it to go ahead, but when we are pulling in clips shot at 50 frames per second that we want to play back slowly we need the timeline frame rate to remain at 25fps – so don’t accept the suggestion of the prompt.

How to create slow motion video with Lumix cameras

In Davinci Resolve a right click on a clip in the timeline brings up a list of options including Change Clip Speed. When you select this a new interface opens, as shown here, that allows us to alter the speed the clip plays back at. In this example a clip recorded at 120fps is being adjusted to play back at 25fps. As 25 is 20% of 120, we adjust the speed to 20% to slow the clip down for 4.8x slow-motion

Ensuring the project frame rate is set to 25fps we then drag the 50fps clip in to it and onto the timeline. In Davinci Resolve you just right click the clip in the timeline and select Change Clip Speed. Then we can select the percentage we want the clip slowed by. If you shot at 50fps and want to play it at 25fps you select 50%, which will give you 2x slow motion. The clip will be able to occupy twice the amount of time in the film once the clip speed is altered.
As your audio track will also be stretched in this process you need to delink the video and audio files before you alter the clip speed if you want to use the audio in the project. This way the video gets stretched but the sound doesn’t, so you can still use the sound over the video if you want to – just be aware that now it will only be long enough to match with half the potential duration of the video.

VFR:

If you used a VFR setting your footage will automatically be shown in slow motion, and so long as you recorded using a 25p codec and your timeline is using 25 frames per second your clip will play at the speed you selected in-camera. If you selected 50%, for example, and a frame rate of 50fps your clip will play back in 2x slow motion automatically.

Lumix GH6 frame-rate options

Many Lumix cameras have exceptional flexibility for those wishing to create slow-motion video, including the Lumix GH5M2 which can manage 2.5x slow motion in 4K 24p with a 60fps setting and 7.5x slow motion in FHD with a 180fps option, and the Lumix GH5s which can record at 240fps for a 10x slow motion effect in FHD at 24p. The Lumix GH6 though can achieve 120fps in 4K for a 5x slow motion effect when recording in 24p in both HFR with audio and AF and VRF modes. It also offers a massive 300fps in FHD for a 12.5x slow motion effect in 24p. Even in the camera’s 5.7K resolution it can manage to record at 60p for a 2.5x slow motion effect, so it really is a pretty amazing slow motion machine.

Slow motion and exposure

Assuming you want to shoot with a 180° shutter, or a shutter speed twice of your frame rate, you will notice that as your frame rates increase you’ll need to add more light, open your aperture or, most likely, push up your ISO setting. When shooting normal footage at 25fps you will probably use a shutter speed of around 1/50sec, but as the frame rate of your camera increases to 50fps you’ll need a shutter speed of 1/100sec. If you display your shutter speed as a fraction you will need to keep an eye on this and adjust accordingly, but if you use shutter angles and wish to maintain a 180° shutter you will notice you lose light as the frame rate gets quicker. Using Auto ISO will help retain the same level of exposure without you having to do very much except make sure the ISO doesn’t creep up beyond a level you find acceptable.

Now do it

Creating a slow-motion video is a whole lot easier than you might think, and your Lumix camera is the ideal tool to help you do it. With so many options built-in all you need to do is pick the one most suited to what you want to do. If you aren’t sure how much slow motion you want it’s best to err on the safe side and record at the highest frame rate your camera offers as then you have the option to try different effects and to speed up your clips or slow them down without losing quality. Once you become more familiar with how frame rates in-camera produce different degrees of slow motion you’ll come to know what’s needed and it’ll get easier to select the right codecs and VFR effects for the effect you want to suit your story.

Lumix Experience Facebook Group

If you have any questions on this piece, or any other, join the Lumix Experience Facebook Group where you’ll find other Lumix users and Lumix experts who will be delighted to help.