Changing StandardAsset ImageEffects on Camera at runtime in Unity

DynamicCameraEffects.cs

using DG.Tweening; // remove this if you're not using DOTween
using System.Collections;
using UnityEngine;
using UnityStandardAssets.ImageEffects;

/// <summary>
/// An extension class for dynamically adding noise to the camera easily at runtime
/// </summary>
public class DynamicCameraEffects : MonoBehaviour
{

    private static NoiseAndGrain _noiseScript;

    private void Start()
    {
        _noiseScript = GetComponent<NoiseAndGrain>();
    }

    public static void BringTheNoise(float newIntensity, float duration)
    {
        DOTween.To(() => _noiseScript.intensityMultiplier, x => _noiseScript.intensityMultiplier = x, newIntensity, duration)
            .SetEase(Ease.OutCirc)
            .SetUpdate(true)
            .OnComplete(RemoveNoise);
    }

    private static void RemoveNoise()
    {
        var duration = Random.Range(0.2f, 1f);
        DOTween.To(() => _noiseScript.intensityMultiplier, x => _noiseScript.intensityMultiplier = x, 0.45f, duration)
            .SetEase(Ease.InQuad)
            .SetUpdate(true);
    }

}