Here's a portion of a render I'm working on, which is backlit from behind by a spotlight with a "Halo" effect applied:
If you look carefully in the background, you'll notice the halo effect is creating "rings" of shadow as it fades. How can I remove these rings and make the halo effect fade out smoothly? I've played around with all the settings I can find without any success.
Here's my current settings for the spotlight: