Caterpillar - learning cycles materials

Hello! This is something I have been working on for a while and am looking for some feedback on where it can be improved.

The main focus of this project has been to improve my materials / get a better grasp of good composition.

Thanks for your help.

UPDATE: added latest render


Looks good by it’s geometry. Be sure to know it’s scientific name if you are basing it off that specific caterpillar. Have multiple references of that specie so you can look at it for reference. Good to know if it has fine hairs along the body like some do. Is it more shiny than most caterpillars. This can be the same for blades of grass if you want to get fully technical within your piece. Just know the how glossy a certain material is by reference and that will give you a great start.

At the moment the specular of the caterpillar looks somewhat muted in the overcast light. Not sure what Genus it is so I can’t really review it fully.

The composition has turned out nice, since I last saw your scene. What could help to improve it further would be a lighting, that matches the backdrop better. The reflections on the caterpillar make me guess, that you used small mesh lights. I believe you could enhance it by using an HDRI for lighting, maybe in combination with a sun.

@RodDavis: Thanks for the response.

So I guess i never really did decide on a certain type of caterpillar to base it off of, but the closest would be like the blacktail swallow caterpillar (at least materialwise) So I’ll probably want to add at least a little gloss to the skin of it. Attached is my current node setup.

@Minoribus: Thanks for helping me out some more. So I actually already have it setup with an hdri and sun light. Should I amp up the enviornment hdri light and tone back the sun?


Hi, Benignbrett, if it is already lit by an HDRI, than maybe another HDRI could help. Here are some humble thoughts about the current lighting setup.


Nice node set up. Yes just mix the current material with a med to high roughed gloss and influence the mix with a fresnel. It should give a nice look and the added spec will add bounce lighting. Of course don’t add too much gloss unless it has a high spec to your version of caterpillar. It is always good to add a certain amount of gloss to most materials. Especially when using subsurface scattering and diffuse.

@minoribus: Thanks for the detailed explanation!
In regard to the spots on the “eye” of the caterpillar, those are actually part of the texture. If it is being misread as highlights on the eye, then I might want to change the design of the pattern on the eye?

Thanks! I’m currently working on throwing a small amount of gloss into the mix.

Ok, so I moved the sun light so that it is shining from directly above and used an hdri that seemed to fit the background image a bit better.


Regarding the Caterpillar’s material, I think you need to take a deep look about how light is reflected and scattered through a caterpillar. It is never just a single color, there are multiple colors involved, that in the end makes the object look somewhat translucent and fleshy.

You should take some time asking yourself, and maybe writing down, how you think the material looks like, in the most simple way. If you go right away into the nodes, you are most likely gonna miss simple observations that any normal person would do. In this case, for example, that Caterpillars are somewhat translucent.

A part from that, you could change that fresnel node and use instead the “Layer Weight” node, which gives you more freedom.

Also, you should blur the background a whole lot. Just google “macro pictures” for references

Muuuuuch better :slight_smile:

I hope you don’t mind that I made some post processing in Gimp to integrate the foreground better with the background. The background has really vibrant colors and a strong contrast. Therefore I used the RGB curves to enhance the contrast in the foreground. And I reduced the green midtones a bit. Additionally I pushed the highlights on the foreground a bit more. Imho it is more balanced between background and foreground now.

You could do that in Blender also with the color correction and the curves in the scene tab or by increasing the exposure or by giving the sun more strength. Ligthing is still a bit flat in your render.

I think the black outlines, which you mentioned in the other thread for the compositor, have something to to with how premultiply is set in the alpha over node.

Because I’m still bothered by the white spots I painted them away.

The materials of the grass could use more translucency. Look how the leaves in the background let the light pass through.

Again I hope you don’t mind. In the end it’s all up to you and your artistic decision :slight_smile:

There are work arounds for that, I cant remember atm (havent done a cycle image in months). Im sure a google search helps on that regard. But alpha over sould solve that most of the time.

I did a google image search for ‘caterpillar macro photography’ and came to the conclusion that your background might be too light and too in focus. I know the background is already out of focus but maybe it could do with being even more blurred.

As others have mentioned, the caterpillar material seems a bit too ‘hard’ and plasticky, as if we’re looking at a toy plastic caterpiller. I’d explore using some sort of real or fake SSS for the caterpillar.

Going back to the background, I’m wondering if you need the hassle of the HDR background at all. <ight be easier, more realistic and easier to light if you do something like Gleb does in his tutorial about nature renders.

Thanks for the responses everyone!

Yeah, I at one point had played around with translucency but just couldn’t get it to do what I wanted it to. However, I’ve learned a lot since then, so I tried my hand at it again, so as to include multiple translucency and still retain the crispness of the patterns on the caterpillar. I think its looking a bit better now. Thanks!

@Minoribus: I love it when people take the time to manipulate my images in order to more easily get a point across, so no worries. Since the white dots bugged you so much(and probably not just you) I removed them. I’m trying to keep the eye of the caterpillar interesting, as it is the main focus of the composition, so I changed up the pattern.

@Bliz: I’ll play around with that tutorial and see if I like how it looks with my caterpillar. Thanks!

I’ve since darkened the background to make it not draw so much attention from the foreground. I’ve also added translucency to the caterpillar.

Here is a somewhat low sample glance at where it is at:

I still need to add a bit more contrast to the lighting. It is feeling a bit flat

I’m not sure I like the composition as much with it cropped close like in this render, but I figured I’d try it out.


Yes, it is looking much much better now! Before, I had issues with the shadows that were being produced on the caterpillar, because they were mainly a shade of black. Now, the shadows are consistent with the color of the object - green shadows.

Now, I would say try to fix the frame to a 16:9 composition, and study/use the golden ratio of composition. It should fix some things.

Also, the shader of the leaves annoy me a little. They dont convince me that much. I would love seeing the reference to understand why I feel them off.

So I messed around with the composition using the golden ratio. I like this composition a lot more, though I the only potential problem I see with this one is that there is no leading room in front of the caterpillar where it is “looking.” Let me know what you think.

As for the leaves, I think they are looking better, but I included the background as reference anyways. (I’m sure some blemishes would make them look a bit better as they are perhaps a bit too clean as is, so maybe later I’ll add some)


Its skin kinda looks like clay, most of the caterpillars i have seen have a sort of rubbery look with a bit of gloss.

Overall very nice work!

I agree with you, everything looks great except for the caterpillar material, you need to add some specular, maybe an Anisotropic Shader could work (with Fresnel as the Mix Value), also the SSS shader need some improvements, maybe change the Radius color, remove the Fresnel as the Mix Value, increase the SSS scale and use pointiness to control the change in color of the caterpillar (or you can paint the color texture).

Also, you can add tiny white fur around the caterpillar (use a Hair Shader set in transmission)

There’s some information in this blog if you’re interested:
Also, here’s a photo for reference:

Thanks for your comment!

I changed the glossy settings a little bit. Hopefully it looks a little less like clay now:

Also, I would like to hear peoples opinions on the composition of it.


EDIT Added a higher resolution/samples image.


Great progress and I like the composition much better, because you have three “layers” now, fore-, mid- and background. And I like the new eye texture.

For the material of the caterpillar you are really close to the real thing, imho. There are so many different species of these. Perhaps I would experiment with some mixed in translucency, to make it more fleshy.

Again, great progress.

Thanks. Yeah, I like the added depth with the foreground.
Composition-wise, I was trying to use the golden ratio, and hopefully I did it correctly?

I increased the translucency on it, made the hairs on its body thicker, and decreased the saturation of the hairs on its body as they seemed to stand out more than the ‘eye’ of the caterpillar.