Iridescent Shader

Hi, I’m trying to emulate with nodes a shader like the dogbane beetle in the pictures. I’m sure you can tell which one is my latest attempt. Any advice crits and suggestions on the material are greatly appreciated. the modeling is nowhere near complete. seems like it’s still missing something. a few things I’ve figured out that make it complicated.

  • a glossy sheen with a very dark material underneath
  • difficult gradiant falloffs
  • a bumpiness underneath the glossy material (i.e. most bump normal calcs are affecting the surface of the gloss, not the surface of the ramp material underneath.
  • weird filtering of light and reflections

once I get this base material I intend to alter it for the head and legs. the body of the shell has that reddish color but the head casing is more blue to green. I’m curious to know if I can do it all with procedurals, so far I think it’s promising. but tell me if uv is needed.


This looks good. :smiley:
My suggestions for the material would be:

  • Give it a harder specularity and more mirror reflections.
  • Make it reflect some yellow light.
  • Try to sharpen the transitions between the different colors. At the moment there are a lot mixed colors which do not look as good as the clear colors of the photos.

i really think it needs some HDRI in order to get that reflectiveness that makes it look so cool. looks good, but doesn’t have that ‘oomph’ that natures has. can we see it from another angle, like the top of the shell?

I see you have a new thread of this… well also I think you will have to make a map/uvmap, to have certain places with certain gradients of color… because in the top pic the beetle has the red on the wings/body, and the head and legs are bluish… so it is just something to look into… This site helps describe how beetles get there iridesence… :

that might help… might not…


  • larger, dotty pores on the surface - you can actually see the dots of colouk on black in the photos.
  • Black not blue

There is a online blender material collection where they had metallic, gold AND for you an iridescent soap bubble or opal glass material… here… takes a long time to lad and even then you have to slash on the icons with a mouse to get them to show up… EDIT actually maybe combine the orange surface and the opal colours…

In Pixar’s Bug’s Life, Dim’s shield (the dung beetle), has a very nice to almost photoreal irridiance shader. I should search for that shader IF it is out there on Google.

thanks for the tips guys… gotta find a job first though. please post any pics/.blends you make or find. this kind of shader would be useful for all kinds of stuff too.

what’s the best way to fake HDRI in blender internal? I want to use nodes but yafray doesn’t support them. environment mapping? I want IBL too - oh maybe AO? does AO work with image maps?

I had the idea once of achiving this with several ramps mapped to reflection, or somthing like that…
Would not it work? (have not tried this)

Be well

Be well.