Make a colour fill to start painting on. Pick a colour and go to the Color tab. Open it and select Fill object, making sure that only RGB is turned on. If M or MRGB is on, it will not only apply colour to your model but also the material/matcap that is assigned at that moment. This isn’t easy to work with when you want to crack out render passes at a future stage. Now you can start painting with PolyPaint. Why the fill? Well, it’s always easier to paint on a coloured ZTool than on a white object – and this way you will never have any white spots left on your model.
I paint in some main colours that I’ve selected from reference pictures. Use the standard Alpha 24 and 25 and the Stroke mode set to Spray. It works a bit like an airbrush, where you put layer on layer with a low intensity to build up colours. Combine a big brush size to fill in the large area and a smaller to get defined dotted areas. Whiten the face, apply a purple/black around the eyes and a red around the nose, ears and mouth. If you want to use the sharper lines use a standard stroke with a smaller Alpha like the mouth and around the eyes.
Select your SubTool and load the texture via Spotlight. Go to the Texture tab and load your reference, then add them to Spotlight. To toggle Spotlight on and off hit Z, or Shift+Z. Move and scale the picture with the Spot Light Dial to the correct place, drop it on the canvas with the shortcut and paint your eyeballs.
Apply some extra veins and clean up parts of the texture that don’t work. The standard material used for rendering eyes is often the Toyplastic MatCap.
The Cavity mask and Ambient Occlusion mask features are great for adding some extra colour and dirt details into the little cavities and wrinkles you’ve sculpted. When a mask is applied, turn off mask visibility, colour pick a darker colour on your sculpt and paint in the cracks and creases you’ve sculpted with a very low RGB value. You can easily colour in too much, so keep working in transparency, building colour on colour. Inversing masks can always be used to highlight some areas with a light tone if you feel this is needed.
I paint in some very opaque veins and some freckles on the skin with the Standard brush, Alpha 38 and using a low RGB intensity with purple, red and brown colours. Try to break the symmetry of your texture with the details. The global colour scheme will be quite symmetrical, but it’s all in the details.
The final image is composed of different render passes with and without PolyPaint turned on. First some Standard BPR renders and shadow passes with different MatCaps are used in Multiply mode. Rim light renders are mostly metal or shiny MatCaps, so you can easily move your light around your ZTool. These are used as layers in Screen or Lighten mode. The Wax, Cavity and SSS renders are used to colourise and make your cavity details pop. Finally I use a BPR mask and BPR Depth map to add some DOF using Lens Blur in Photoshop. I combine these with a hand-painted backdrop and an extra texture layer is applied to add some grittiness to the final picture.