Posted by Farrah Penn - Contact Author
If you are searching for an easy solution, click here: adjust speed to slow down DJI footage
Applying slow motion is one of the tricks to make your video looks professional and cinematic. Newly released DJI Osmo Action has slow motion mode built-in, but you can also shoot in high FPS and slow it down in post editing. Is there any difference between shot in slo-mo and post editing to adjust video speed? How to edit slow motion video from Osmo Action footage? Read on if you have these questions.
In-camera Slow-Motion vs Adjust Speed in Post Editing, Which One Shall I Choose?
Unlike GoPro Hero series, DJI Osmo Action has slow motion mode built in. If you shoot in slow motion, you can view the slow motion effect when copy the video from SD card to a computer.
For GoPro action camera series, some user thought slow motion not working due to some errors. In fact, Hero series don't have slow motion mode. People seeking help online are being told that, "You want slow motion in GoPro? Then shoot it at high FPS such as 120fps, 240fps". Some users misinterpret it as: video is slowed down if you shoot video at 120fps or 240fps. Actually, high FPS is a prerequisite for smooth slo-mo, not the end product. You have to adjust speed in post editing to have that slow motion effect.
To conclude, on DJI Osmo Action, you can either 1) shoot in slow motion mode (limited to 4x and 8x for 1080p and 720p) or 2) shoot at high FPS and post edit it into slow motion with more customizable options. As for GoPro Hero series, go for post editing as there is no in-camera slo-mo (hint: you can adjust playback speed on Hero7, but when you copy the clip to a computer, it's normal speed).
Slow Motion Mechanism Explained: Why high FPS, Can I Shoot at 30 FPS and Slow it Down?
Not interested in theory? Skip to step-by-step tutorial on how to slow down a video>>
Theoretically, any video with an FPS of 60, 120, 240 (Or PAL set of 50, 100, 200) can be post edited into a slow motion video.
Let's do a simple math. Say we shoot a 60 fps video, there are 60 frames in one second. If we put the first 30 frames in 00:00:01, and the last 30 frames in 00:00:02, our original 1s long video becomes a 2s long video, so the motion looks slowed down.
How about 120 fps? If your final product is 60fps, now your 1s video spread into 2s with 60 frames per second, 2x slower; and for 30fps final product, it's 4x slower with a duration of 4s.
Now you might already know the answer. With a video originally shot at 30fps, if you spread the first 1s 30 frames into 2s, where do you get those additional 30 frames that don't exist? Though post editing software can provide you with time interpolation algorithm to create additional frame based on neighbor frames, it's still a guess work. Plus, you can't put every 15 frames in 00:00:01 and 00:00:02, because it will not be perceived as a smooth motion to the human eye, but rather a picture-by-picture process.
How to Edit Slow Motion Video with Customizable Options to Adjust SpeedAdjust speed in 1-click to make slow motion with lightweight video speed controllerEasier & fast Solution
If you simply want to slow down Osmo Action footage shot at high FPS, and hesitate to open up the bulky Premiere for a simple task, fast-to-launch VideoProc that comes with hardware acceleration could be a good choice. You can use it as a video speed controller to slow down footage 10x maximally or speed it up to 16x. Needless to say 2x, 4x, 8x is a simple dial with speed adjusting knob.
VideoProc - The One-click Way to Slow Down Any Footage, and Speed Up.
- One stop media transcoder, video editor and screen recorder.
- Easy editing: cut, crop, merge, stabilize, deshake, denoise, add filter.
- Process footage from DSLR, DJI, GoPro, smart phones and DVDs.
- Wide format support with 370+ built-in video audio codecs.
Follow the steps below to alter the speed of a video from DJI Osmo Action, GoPro or any other videos you have at hand.
Step 1. Click Video icon to open up the editing mode. Drag your footage into working area, or click +Video at top left to import it.
Step 2. Click Option > Edit Video tab. Adjust playback speed at bottom left. You can either drag the slider or type in preferred times. Here is a list for your reference.
- 0.1x (10x slower)
- 0.25x (4x slower)
- 0.5x (2x slower)
- 1x (the original speed of video)
- 2x (2x faster)
- 4x (4x faster)
- 8x (8x faster)
- 16x (16x faster)
Step 3. Click Done and choose your desired format and hit run to export the video.
Now that you know how to make slow motion video from Osmo Action footage, you can start to add drama to your exciting sports and action films. But there is always a compromise between high FPS and low light conditions. To shoot high FPS videos, the camera shutter open for a shorter period of time, not enough for the sensor to perceive light, thus end up with grainy footage. Check out this post on Action Camera Settings for Low Light to deal with the problem.