You can slow down motion in Blender primarily by using the **Speed Control** effect strip in the Video Sequence Editor (VSE).
## Slowing Down Video in the Video Sequence Editor (VSE)
Blender's Video Sequence Editor (VSE) is a powerful tool for editing video and audio. To change the playback speed of a video clip, the most direct method is to apply a dedicated effect strip designed for this purpose: the *Speed Control* strip.
### Steps to Apply Speed Control
Here’s how to add the effect strip to your video clip:
1. **Open the Video Sequence Editor:** Ensure you have a Video Sequence Editor window open in your Blender layout.
2. **Add Your Video Strip:** Import or add the video clip you wish to slow down onto the VSE timeline.
3. **Select the Video Strip:** Click on the video strip in the timeline to select it.
4. **Add the Speed Control Effect:** With the video strip selected, **press `Shift + A`**. This brings up the Add menu. Navigate to "**Effect Strip**" and then choose "**Speed Control**." A new strip will appear on a track above your video strip, automatically linked to it.
### Adjusting Speed by Changing Strip Length
Once the *Speed Control* strip is added, its length on the timeline directly governs the playback speed of the video it controls.
* To **slow down** the video, you must **lengthen the Speed Control strip**. This stretches the original number of frames over a longer duration on the timeline, causing them to play back slower.
* To speed up the video (the opposite effect), you would shorten the *Speed Control* strip.
You can easily adjust the length of the *Speed Control* strip by grabbing its end handles (using the `G` key or clicking and dragging) and extending it to the desired duration. For instance, if your original video was 150 frames long, making the *Speed Control* strip 300 frames long will play the video at half speed.
#### Example: Speed and Length Relationship
Here's a quick look at how strip length relates to speed:
| Action | Effect on Speed | Required Speed Strip Length (Relative to Original) |
| :-------------------------- | :-------------- | :------------------------------------------------- |
| **Slow down** | **Decreased** | **Lengthen** |
| Play at half speed (50%) | 50% | Double the original length |
| Play at quarter speed (25%) | 25% | Quadruple the original length |
### Audio Considerations
When you slow down a video that has an associated audio strip, the audio will also be affected. The reference points out the need to modify the audio pitch to match the video speed for consistent playback. You can sometimes adjust pitch within the Speed Control strip's properties or manage the audio strip separately to achieve the desired effect and avoid distorted sound.
### Alternative Method: Using Properties Panel
While adjusting the strip length in the timeline is intuitive, you can also precisely control the speed using the *Speed Control* strip's properties panel. With the *Speed Control* strip selected, press `N` to open the properties panel on the right side of the VSE window. Here, you'll find settings like "Speed Factor" or "Multiply Speed." Setting "Multiply Speed" to `0.5` would play the video at half speed, `0.25` at quarter speed, and so on. Changing the length on the timeline automatically updates these values, and vice-versa.
## Key Takeaway
To slow down motion in a video clip within Blender's VSE, add a **Speed Control** effect strip to your video strip and make the *Speed Control* strip **longer** than the original video strip's length.
