How to create a glowing fog effect

Question

I would like to replicate something like this:

I've started with a layer of graphene from a tutorial (here is the corresponding blender file: blender.freemovies.co.uk/blenderfiles/modelling/chemistry/graphTut24.blend)

The right way to go is probably something like How to create a strong halo light effect?

However, I don't know how to apply that to my problem, as I'm fairly new to blender. Thank you very much for any help!

EDIT: So I managed to get the desired effect using halo+lines (because I like it with the lines, see the blender manual under Halo Rendering. However, that only works using the Blender Render, but I have to use the Cycles Render. I've tried to achieve a similar effect using that render engine (there are lots of ways here on stackexchange), but I cannot get the lines and it doesn't look as nice as using the blender render + halo. What's the best way to start to achieve the same as in halo+lines?

Answer 1

If you want a glare with lines it is easy to do in the compositor.

In your scene add an object and give it an emission shader and use a strength that is more than 1.

Then in the compositor add a glare node in streaks mode. Use the threshold value to determine what values get affected by the glare node (in this example any value larger than 1 will be affected by the glare, darker values will remain unaffected). You can also choose the number of streaks you want:

(click on the image to enlarge)

Now, if what you want is to have is a more realistic "fog" effect, you need an environment (or a domain) with volume scatter. If you use volume scatter as volume for the world, then you can create real volumetrics, in which the suspended particles get lit by the light source and the mesh will create shadows (be ready to increase the strength of your light sources). Think of volume scatter as filling the scene with dust or smoke, the density for volume scatter will determine how hazy it is, usually the default value of 1 is way too high.

(click on the image to enlarge)

And don't forget that you can combine volume scatter with a glare node in the compositor as well:

Answer 2

For the purpose of this answer I will be assuming that what you are trying to achieve is not a post processing effect but a physical fog that glows (in cycles).

To create fog you need to essentially create a smoke simulation, fortunately there is a quick way to do this with the inbuilt cloud generator (blender v2.78).

Create a mesh roughly the size and shape of what the fog will be and then while having it selected press Space -> search -> Generate Cloud

Once you have a point cloud, select its material, delete the bottom part of the nodes except for point density and replace them with a simple Volume Scatter node mixed with an Emission node with the factor being the point density connector.

Tweak the values and nodes to your liking/scene.

Please ee aware that the fog will now realistically emit light and illuminate your mesh, as it is a "real" volumetric object, not a 2D effect.

PS: This works as well with animated particle systems, just switch the point density node to particle system in the material of the particle system that you want to use.