Is it compositing that is used after a render for this affect?

I was wondering, I am new and been modeling for a few months now. I have been learning about orange and teal lighting but, should I learn what render passes ,dust and particles, curves along with volume metric lighting to get this affect from Red Cartels image that is below? [ATTACH=CONFIG]286324[/ATTACH]

My first guess is that the effect you are referring to here is mostly bloom. That would be a compositor step (though you may be able to get something nice with the new volumetrics…but be prepared for very long renders and a lot of noise :wink: )