I am trying to make an image similar to this one: https://i.stack.imgur.com/CBxuE.gif
But with this model: (removed link so I could post link to blend file)
However, I would like it to have a transparent background. I have found this question on here:
And I implemented the second answer with the blue glowing cube, but this isn't the effect I'm going for. What I want is just the glow on the outside of the sign, but the above method generates a glow that also affects the black letters and outline, and gives it an "out of focus" or "squinting" look.
To achieve the red and white animation I am using a background plane and moving it from right next to the sign to far away, so the glow gets bigger. What I would like is to somehow keep this glow in the render but loose the plane and have a transparent background instead.
I would like to use blender for this because it's what I'm sort of familiar with, but since this a 2D image and not a model maybe it would be easier to render without the back plane and use GIMP or add the glow through post processing? I'm a total noob when it comes to nodes so any help or pointers would be appreciated. Thanks!