As with the modelling, I don't feel it’s necessary to give you an in-depth rundown of my Mudbox sculpting techniques. There are plenty of digital sculpting tutorial videos out there, and this is the first time I've ever really used it in a project so I can’t really offer you anything that I'm sure a far more experienced digital sculptor could. I have, however, included a few videos showing the various layers in Mudbox, and also the export settings that I used to get the displacement map into LightWave.

Fig.17 shows exporting the model from LightWave for Mudbox (click on image to download movie).

Fig.18 shows the displacement layers and map export in Mudbox (click on image to download movie).

Fig.19 shows the Mudbox head.

As you can see from the next video (click on Fig.20 to download movie), I used the shader node system in LightWave to apply the displacement map. I did consider simply exporting the high-density mesh from Mudbox, but eventually I want to animate this mesh, so I really need to keep the low-res geometry (Fig.20).

I started this project with the intention of trying out LightWave’s node based shader system and, more specifically, the simple skin shader. I had done some work in the past with MISS shader in Maya and was becoming increasingly frustrated with G2's flaky performance. The simple skin shader is very similar to MISS in Maya; it’s fully supported by FPrime so it’s really simple and easy to make changes and see them update immediately, even with multiple bounce radiosity enabled. Before I start applying textures and shaders to any character model I begin by setting up the scene with a single distant light set to 100%. If you can get the skin to look good with a simple lighting setup like this, it’s only going to get better when you add some radiosity, rim and spec lights later on.

See Fig.21 for the node setup.

This channel is used to plug the base colour map into. I used a setting of about 50%. Diffuse Epidermis and Sub-dermis Visibility should add up to 100%.

This channel controls how much diffuse shading there is on the bump map.

This is the colour of the specular highlight. I always use a pale blue for the spec colour.

Plug the Spec map into this channel. As you can see from the diagram, I placed a colour tool into the flow. This allowed me to adjust the brightness and contrast of the image, just in case I needed to fine-tune the spec later on. Don't forget that if you’re plugging a colour map into a scalar channel, like spec, then you should use a colour scalar node.

For the Gloss map, once again, I used a colour tool node. As I explained before, I used the same map for the gloss and spec, but cheated by adjusting the brightness and contrast of the gloss until it looked correct. This was made very simple by using FPrime. As you can see, the updates on the rendered image appear almost immediately, which also saves a lot of time messing around between Photoshop and LightWave. This type of cheating is just one of the many advantages to using the node shader system – it's much better!

This setting allows the specularity to vary according to the viewing angle of the surface. I set it to 35%.

The refraction index is a measure for how much the speed of light is reduced inside the medium; in this case the light travelling through the skin. The refraction index of skin is generally believed to be between 1.37 and 1.42. This shader had it set to 1.37 when I loaded it up, so I just left it where it was as it seemed to work pretty well.

The epidermis is the colourless, translucent top most layer of tissue; it allows a lot of light through to the fatty sub-dermis layer below. I set the visibility to 30% and the distance to 1.5mm – as is the default on the shader. When changing the distance settings you should always take into account the scale to which you model is made. I modelled my head to a realistic scale and as such the default settings were pretty much right from the offset. Gamma I left at 1.0, and I changed the samples to 4. This was simple for speed at first, but when I did some render tests I couldn't really see any difference between 4 and 8, so I left them at 4.

This is the relatively thick, fatty bloody layer below the epidermis. It contributes quite heavily to the reddish colour of the skin as the light passes through the capillaries where the light is “tinted” by the blood. I set this to 20%, making the overall value of the Diffuse Epidermis and Subdermis up to 100%. Again, I left the Distance at the default 2.2mm, the Gamma at 1.0 and, as before, changed the samples to 4.

This is the intensity of the bump map. I increased it to 150%, but this value depends on how much contrast you have in your bump map. The only real way to figure this one out is to do some renders and see what looks good.

By default, the simple skin shader uses reflection as well as specularity, however, I really didn't want to use reflection for this image … You are more than welcome to fiddle around with it and try to make it look good, but I kept getting rendering artefacts in FPrime and it was taking far too long to render out the reflection noise with multiple bounce radiosity turned on, so in the end I just went for spec. If, like me, you decide to turn the reflections off, you have to set the Mode to Spherical Map and Reflection Image to (none).

This is my favourite part of the whole process – it's where all the laborious modelling and texturing finally pays off! Personally, I could spend days fiddling with lighting rigs and settings. For this image I wanted something that would show the face off but remain fairly gloomy and dark. I wanted him to look lost and alone. In the end, I went for quite a stark contrast between light and dark, keeping his entire left side in shadow. The rig was very simple: I used one area light for the main light source and a distant light behind his head to hint at some kind of rim lighting. The rest of the illumination was provided by the background Monte Carlo radiosity, set to 3 bounces, using only a grey background colour.

The camera setup was also very basic; the focal length was set to 85mm, roughly around the same as most portrait photographers use. Because I was rendering it with Fprime I didn't need to worry about any of the AA settings, as FPrime continually increases the quality of its AA with every pass that you leave it to do.

The image was rendered using FPrime, which is, in my opinion, the single greatest plug-in ever invented! I can't imagine working without it. Being able to render a scene in seconds with full radiosity, reflection, SSS and displacement, is unbelievably helpful when you’re setting up a render. It allows you to tweak to your heart’s content and not have to worry about lengthy low-res preview renders every time you need to see an update. If you’re a LightWave user, I can’t recommend this plug-in enough. For the bulk of the rendering I used the FPrime preview, but when it came to the final render I used the FPrime Render plug-in as it allowed me to set things like lighting quality, and also seemed to render slightly faster – and with better antialiasing – than the preview.

See Fig.22 for the lighting setup and properties.

See Fig.23 for the camera settings.