I started to experiment a bit with basic shapes and Blender’s Compositor - that’s what I ended up with. Entirely made in Blender.
Small:
Large:
Nice colors.
Nice work!Can you post up a node setup?
Nice, though I could see a little less usage of the dark bands replacing more of that with vivid color, and the bands being softer.
Thx for all the comments. 
Sure, although it is very hackish. As I said I just experimented without any concept in mind, so I changed the whole colors of the image in a way that would have been easier in the materials. 
Nice work!