This plugin will ensure your comp is not exceeding specified colors values. It will legalize those values and let you specify which should be the whitest and blackest color.

A tool that lets you know which part of your picture is too bright or too dark by pointing the bad pixels directly on your footage. Similar to the way zebra-stripping works on digital cameras.

Learn quick tricks of using Particular.
Attach the particular to butterflies leaving trails.
by Shoaib Khan

Randomly shifts the selected layers in time within user defined range.