Physical Accuracy: These shaders are "physically accurate" so to speak, meaning they're built upon the concept of tree growth. Therefore they function most accurately when applied to models that are constructed as they would be in reality. For example, if I were to model a dining table with the intention of using one of these shaders on it, the table would need to be constructed with separate pieces of proper orientation, just like a real table is constructed. If your 3D model is one solid piece of geometry, the shaders will operate as though the table was hewn out of a single log.
Proper orientation: For accurate results, make sure your model's length (where you want to see your grain pattern) is pointed in the local Z axis. See the image to the upper-right. Notice how the correct board emulates correct Z-axis orientation, as though it were a piece of lumber that was cut from the tree.
Scale: The scale of the wood texture is significantly influenced by your object's scale. Thus the first setting you'll likely need to adjust after applying one of the hardwood materials is the "Grain Scale" slider (called "Tex Scale" in the CGC_hardwood node).
Appending into your Blender scene: In Blender, go to File > Append and select all or desired items in the "Node Tree" and "Material" folders of the "CGC_hardwoods.blend" file.
CGC Hardwood Settings
Shader Socket: Complete shader output.
Texture Socket: Only the texture output.
Normal Socket: Only the normal/bump output.
Splotchiness Factor Socket: Texture output of the Splotchiness setting.
Tex Trans X: Translation of the object texture coordinates in the X axis.
Tex Trans Y: Translation of the object texture coordinates in the Y axis.
Tex Trans Z: Translation of the object texture coordinates in the Z axis.
Tex Scale: Overall size of the procedural texture coordinates.
Tex Rot X: Rotation of the object texture coordinates around the X axis.
Tex Rot Y: Rotation of the object texture coordinates around the Y axis.
Tex Rot Z: Rotation of the object texture coordinates around the Z axis.
Global H: Overall hue shift of wood texture colors.
Global S: Overall saturation of wood texture colors.
Global V: Overall value of wood texture colors.
Primary Grain Color: Color of the space between wood rings.
Secondary Grain Color: Color of wood rings.
Fine Grain Overlay: Overlaid color of tertiary grain pattern.
Ring Count: Quantity of wood rings.
Ring Jitter: Intensity of noisy breakup for wood rings.
Ring Jitter Scale: Size of the noisy breakup pattern.
Ring Fiber Scale: Size of fibrous pattern in the grain.
Ring Spread Variation: Randomization of ring spacing. Note, this will likely require additional manipulation of "Tex Scale" and/or "Ring Count" settings.
Ring Thinning: Thickness adjustment for wood rings.
Pores: Intensity of pore contribution to the grain pattern.
Pore Color: Color of the pores (Multiply blend mode).
Pore Scale: Size of pore pattern.
Grain Stretch: Stretch or compression adjustment along the length of the object (Z axis).
Randomize Grain: Randomization of grain pattern. Useful as a "seed" value on a single object or as a variety among multiple objects sharing the same shader.
Randomize Color: Randomization of saturation and value of overall color. Like "Randomize Grain", this setting is useful among multiple objects sharing the same shader.
Streaks: Intensity of streak overlay pattern.
Streak Color: Color of streaks (Overlay blend mode).
Streak Scale: Size of streak pattern. Functions visually like a seed value.
Streak Contrast: Adjust the hardness of the streaks' edges.
Figure: Intensity of wood figuring.
Figure Scale: Size of figure pattern.
Figure Stretch: Lower values make for a tiger-stripy pattern, higher values compress the pattern into a curly type pattern.
Figure Shape: Subtle adjustment of figure pattern appearance. A value of 0 is blurrier while a value of 1 is sharper.
Figure Grain Jitter: Intensity of the figure pattern's influence on the wood grain pattern. A value of 0 is no influence while higher values will manipulate the grain.
Reflection: Intensity of glossy reflection.
Reflection Roughness: "Blurriness" of reflection; lower values result in clearer reflections, higher values result in blurrier reflections.
Fresnel Blend: Bias toward lower or higher registers of the fresnel reflection.
Reflection Splotchiness: Surface breakup of reflection values.
Splotch Scale: Size of the splotchiness pattern.
Anisotropy: Intensity of anisotropic reflection contribution.
Anis Rough: Blurriness of anisotropic reflection.
Anis Amount: Intensity of anisotropic effect.
Anis Rotation: Angle of anisotropic stretching.
Bump: Intensity of bump texture.
Bump Grain Smoothness: Defines how much influence the grain pattern has on the bump. Lower values mean more grain contribution, higher values mean less grain contribution.
End Grain Bump Increase: Additional bump intensity for end grain.
Pore Bump: Intensity of pore influence in the bump map.
Speed Boost: Exclusion of bump map in non-camera-ray calculation. *Can* speed up render times but isn't overly reliable.