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# imageSequenceFrameRateVariation

The range, in frames per second, of randomized frame rates for particle image animation. Animatable.

```
var imageSequenceFrameRateVariation: CGFloat { get set }
```

## Discussion

Setting a nonzero value for this property randomizes the effect of the [`imageSequenceFrameRate`](/documentation/SceneKit/SCNParticleSystem/imageSequenceFrameRate) property. SceneKit randomly adjusts the animation speed for each particle by up to half the [`imageSequenceFrameRateVariation`](/documentation/SceneKit/SCNParticleSystem/imageSequenceFrameRateVariation) value. For example, if the [`imageSequenceFrameRate`](/documentation/SceneKit/SCNParticleSystem/imageSequenceFrameRate) value is `10.0` frames per second and the [`imageSequenceFrameRateVariation`](/documentation/SceneKit/SCNParticleSystem/imageSequenceFrameRateVariation) value is `10.0` seconds, each particle animates at a random rate between `5.0` and `15.0` frames per second.

The default value is `0.0` frames per second, specifying no randomization.

You can animate changes to this property’s value. See [Animating SceneKit Content](/documentation/SceneKit/animating-scenekit-content).

---

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