Going nuts trying to figure this out!!

I’ve been using Blender for a little while and found it great to use and much easier to understand that some of its competitors.
Through YouTube video tutorials and tutorials on www.blenderguru.com, I have learned a lot including how to add texture and materials to models.

Recently I modelled a sci-fi space scene: A large space ship and a smaller shuttle (for scale). Everything looks good and I am relatively satisfied with what I’ve done but I want to get into compositing in order to add special effects to the models. From the rear of both ships I have afterburner cones that have a gradient material added to them and at the front of the main ship I have a light beam shooting forward. These are the items I wish to post process and add effects to, like blur and glare.

I tried to follow a blenderguru video on the subject but it didn’t really help as much as I would have liked as I need someone to explain how the compositor works.

I have questions:

  1. Do I have to separate the afterburners from the light beam and place them on separate layers?
  2. Should I separate the background image plane from the spaceships and place them on separate layers?
  3. Should all the layers be placed on individual render layers and then be individually rendered before opening the compositor?
  4. In setting up the nodes for compositing, should I add a render layer node for each render layer, and if so how do I link all of them and their individual effects node to the final composite node? (I guess I need a street map!)

If anyone can help and give me advice, suggestions or point me in the right direction, I would appreciate it.


Glare works on brightness of the source image to determine what gets blurred (glared). But if you want a different amount of glare on bright things in the shot you may have to split them onto their own layers.

However when you do this you get an alpha channel for each layer that isn’t a background. Now when you add glare it may not work correctly into the alpha region, meaning the glare effect may not be apparent when you “alpha over” (mix) the individual layers.