Preview Wax will apply a wax-like appearance to the model’s materials in real-time through the Preview render. This means that the effect will be visible even during normal sculpting and scene set up. For Preview Wax to display, the WaxPreview option must be turned on in the Render > Render Properties menu and materials must have the Strength slider in the Material > Wax Modifiers menu set above zero.
The Strength slider defines the amount of wax effect to apply to the model. A high value will make the model appear to be very waxy while a smaller value will result in a subtle SSS-like effect.
The Fresnel slider defines if the wax effect will be applied on the surface of the model that is facing the camera or on the surfaces of the model angled away from the camera. A negative value will affect the front of the surface while a positive value will affect the sides of the surface.
The Exponent slider sets how fast the Fresnel falloff of the wax effect will be applied to the surface. In other words, how sharply a change in surface angle will affect the wax.
The radius slider defines how far the wax effect spreads out from the areas where your other settings determine should be waxy. A low value will reduce the area of the wax while a high value will increase the amount of wax rendered across the surface of the model.
The Temperature slider affects the wax temperature, similar to the light temperature found in photography. A negative value will add a cold (blue) tint to the wax while a positive value will add a hot (red) tint.
Max Depth Tolerance
The Max Depth Tolerance slider adjusts the wax maximum 3D difference between pixels during a BPR render when the Wax Modifier is turned up.
For example, if you were to look at the DemoSoldier from above, the nose pixels and leg pixels will be relatively close in the ZBrush document; however, in real 3D space the legs and nose would be far apart. This slider can be adjusted to so that the true distance is more accurately interpreted and the wax render more realistic.
Reference Guide > Render > Preview Wax