# useUnscaledTime

> When true, use the unscaled delta time to simulate the Particle System. Otherwise, use the scaled delta time.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine](/engine/6000.5/script-reference/unityengine.md)
* **Assembly:** UnityEngine.ParticleSystemModule

```csharp
public bool useUnscaledTime { get; set; }
```

### Remarks

This is useful for playing effects whilst the game is paused and \[\[Time.timeScale] is set to zero.

### Examples

```csharp
using UnityEngine;
using System.Collections;

[RequireComponent(typeof(ParticleSystem))]
public class ExampleClass : MonoBehaviour
{
    private ParticleSystem ps;
    public float hSliderValue = 1.0f;
    public bool useUnscaledTime = false;

    void Start()
    {
        ps = GetComponent<ParticleSystem>();
    }

    void Update()
    {
        var main = ps.main;
        main.useUnscaledTime = useUnscaledTime;

        Time.timeScale = hSliderValue;
    }

    void OnGUI()
    {
        GUI.Label(new Rect(25, 40, 100, 30), "Time Scale");
        hSliderValue = GUI.HorizontalSlider(new Rect(105, 45, 100, 30), hSliderValue, 0.0F, 10.0F);
        useUnscaledTime = GUI.Toggle(new Rect(25, 75, 100, 30), useUnscaledTime, "Use Unscaled Time");
    }
}
```