Some have asked for my fur shader definition so I am sharing more details on my fur shader here.
Though I had tweaked everything from the skin to the whiskers to the eyes to the claws to the fur, in this post I am only talking about the fur. The Lion is the Feliidae By AM - Lion LAHM version (Lion - LAMH - Color Scheme 1) available at the Daz3D store. I never render in IRAY so I will not be providing any comparision with IRAY. I do believe the IRAY material is better because you can color the hair root and tip diffrently which obviously we can't do in the Daz Octane plugin. So the aim here was is to see how to make the fur look good in Octane. Also when I convert the hair to Fiber Hair using the LAHM plugin I increased the hair count by a lot. E.g. for the boby hair group, I added a million extra hair strands. I did so so that the fur looked more dense. Do note it increases the memory requirements. So if your GPU cannot handle the increase in hair strand count, don't do it.
The setup is simple. One Diffuse Material and one Secular Material node. The Diffuse Material node provides the color and sheen and the Specular Material node provides the highlights and translucency. The definition of the shader is slightly different from the wolf fur shader I had used to render the wolf as shown in viewtopic.php?f=44&t=73819#p383530. Like I had said depending on the color of the diffuse material / texture some adjustments may be needed.
The Diffuse Material node is fairly simple. I used the LAHM hair texture that came with the lion and just adjusted a bit to enhance it to my liking using the color correction node. This Color Correction node you will have to adjust to your liking. I then simply plugged it into the Diffuse pin and Transmission pin of the Diffuse Material. Next I added a Absorption Node and for the Absorption pin I used the same output from the Color Correction node that I used in the Diffuse Pin. I Invert absorption so that the color absorbed is the opposite color of the texture and the final result is the color of the texture. It may be not very apparent with the texture I am using (or with what you might use) but try as an experiment with a solid color like Red and see what invert absorption - ON / OFF does. As the hair stand is very thin, I used a Density pin of .1. You can experiment with different values here. I used small value as i wanted translucency. Finally I added the sheen. This again you can adjust to your taste. For me I kept the Roughness pin to .3 and Sheen pin to RGB 72 72 72.
- Diffuse NGE
Next was the Specular Material Node. This also has a fairly simple setup. In this I used RGB 255 244 218 as the Highlight pin color so that the highlights were not pure white (Slight yellow tint). Again you can experiment and see what you like. For the Transmission pin, I used another Color Correction node that took the output of the Color Correction node that I used with the Diffuse pin, as input. I wanted more transmission so using it I brightened it up a bit for the face fur. Roughness pin I set to 1 as I wanted the highlights to be fully spread along the hair stand. Also on such thin geometry as a hair strand, using 1 gave a better result than setting it to a low value. You can set it to .1 etc. to see the affect it has on the highlights. I finally added the Scattering node to complete the SSS. In the Scattering node I kept the Density pin as .1, Absorption pin as RGB 0 0 0 and Invert Absorption as ON. You need to do this other it affects the output. If you OFF it, you will see an immediate affect on the render. You can experiment on this to see how it affects the output. For the Scattering pin I used RGB 255 255 255 and for the Scattering direction pin I used -0.75. Once again you can experiment with these values to see how things change in the render.
- Specular NGE
Finally I mixed the Diffuse Material and Specular Material mode with a Mix Material node and set the Amount pin to .7 (70% mixed with 30% Specular).
- Full NGE
The Lion had 4 fur group. So I applied the same definition to all 4 and then tweaked individual once as needed. One other thing you need to take into account is the lighting. I am using a VHDRI (Very high dynamic range image) so the light quality is excellent. Hence the render looks good. Your lighting will definitely affect what result you see so I would recommend using HDRI instead of the Octane Daylight. Also you at least need to use Path Tracing as the Kernel. I also use higher Diffuse depth / Specular Depth / Scatter depth (Under Path Tracing in the Rendersettings Tab) than recommended. Mine is set to 48, 48, 256 respectively. It may be too high but for my rig, the rendering is still very fast. The renders you see here took around 30 seconds at 1000 samples for 1080x1080 images. I do have 4 Titan RTXs.
The SSS effect will be more apparent if the light is behind the Lion. Here I did not do that. The light is just to the front left and front right of the Lion from front.
Following are the sample images I made:
Light from front left of the lion :
- Lion - Full
- Render Passes for lion
- Lion Face closeup
- Render Passes for face closeup
- Lion Legs closeup
- Render Passes for legs closeup
Light from front right of the lion :
- Lion - Full
- Render Passes for lion
- Lion Face closeup
- Render Passes for face closeup
- Lion Legs closeup
- Render Passes for legs closeup
I am attaching my material for the Lion body fur. Do note I have removed the actual texture I used as it is a paid item. You can plug in your texture into the texture node. From the Octane->Materials Tab, there is a Import button at the bottom. You can click that and then select the ORBX that you saved from this post. It should appear as an unused material. You can then drag and drop as necessary.
I am sure someone can improve on this result and if you do so, please do share like I am sharing here.
Btw. always use render passes like Reflection / Reflection Direct / Reflection Indirect / Transmission / SSS etc so that you can actually see how the light is affecting the material you are using. This is specially helpful when you are trying to build your own material. I use a lot more of the passes. I will create another post to show how and why I use them.
Regards,
Rajib
PS : It looks like the shader will not work with the Daz Studio Hair. Probably because the Daz Hair is not natively supported in the Octane Plugin and hence the materials don't work properly. Even if I use a patterned texture with the Daz Hair, I only get single color. The shader works fine with the LAHM Fiber Hair.
