Every new scene, by default, contains a single material layer called the 'Base Material' that effectively shades the entire scene until material tags are defined by the user, limiting materials and shading to specific surfaces. The 'Material' layer contains all the basic properties necessary to produce a rendered surface. There are many settings inside the 'Material' layer and as such, its property form is divided into two sub tabs 'Material Ref' (Reflected) and 'Material Trans' (Transmissive). The first tab contains all material attributes that impact how much light is reflected from the surface such as Diffuse, Specular and Mirror reflected light. The Transmissive section controls how light is transmitted through a material such as Transparency and Subsurface Scattering. In addition to these settings, nearly all material properties can be controlled via a texture -bitmap or procedural. Create a new texture layers and set the 'Effect' to the material property you wish to control. For more on adding layers and setting their 'Effect', please reference the Shader Tree page of the documentation.
Material Ref
BRDF--
Diffuse Amount: In the real world, all objects absorb certain wavelengths of light while reflecting others. The light that is reflected is what we see as the color of the object. The 'Diffuse Amount' acts as a multiplier to the 'Diffuse Color' setting, determining how much of that light is reflected from or absorbed by the surface. A setting of 100% would return the same value as the diffuse color value when lit by a pure white light at 100% intensity. A 'Diffuse Amount' of 50% would appear half as bright under the same light as it would only return half of the light bounced from the surface, and so on.
Diffuse Color: The 'Diffuse Color' setting defines the color of the surface when lit by pure white light sources be it direct or indirect. This is effectively the color of your object, representing the light that bounces from the surface. Diffuse colors can also be driven beyond traditional color space into high dynamic range values by applying Diffuse Amounts over 100%.
Diffuse Roughness: Extremely matte surfaces, such as stone, concrete or plaster, reflect light very differently than smooth or glossy surfaces, such as glass or plastic. This is because on a microscopic level the matte surface is actually quite rough, spreading the light outwards, making the surface appear more flat. The 'Diffuse Roughness' setting aims to simulate this microscopic roughness effect by modifying the standard shading model, producing a more believable matte surface. A value of 0% disables the effect, while values above zero increasingly produce a rougher, more matte surface. Since 'Diffuse Roughness' simulates a lack of Specular, it is best applied when the 'Specular Amount' is 0%. -- (image examples below)
Conserve Energy: When enabled, the 'Conserve Energy' setting, in its most simple description, maintains a physically accurate blend of diffuse and specular light reflection over the surface of your object. As reflection amount increases at glancing angles (like when the 'Fresnel' settings are used), Conserve Energy realistically adjusts the amount of diffuse to maintain an accurate balance between the two producing extremely realistic results.
Conserve Energy affects three material channels. It changes the Specular Amount (which is derived itself only by direct light source items), it reduces the Diffuse Amount based on the Specular Amount and the Fresnel setting and it also reduces Diffuse Amount as the 'Reflection Amount' goes up. All of these things result in a more physically accurate and realistic result.
 Diffuse Roughness 0% |  Diffuse Roughness 25% |  Diffuse Roughness 50% |  Diffuse Roughness 75% |  Diffuse Roughness 100% |
Specular Amount: In the real world specular highlights are the reflections of very bright light sources on a surface. How these reflections spread over a surface tell a lot about that surface, be it shiny or dull, smooth or rough. 3D programs simulate this reflection with these 5 settings- Specular Amount, Fresnel, Specular Color, Roughness and Anisotropy. Generated only from direct light sources in a scene, the 'Specular Amount' is multiplied with the 'Specular Color' to create the overall rendered result. Increasing the value will result in a more intense highlight while decreasing the value will mute the effect. When this value is 0% the Specular Color, Roughness and Anisotropy controls become disabled and specularity is not calculated.
 Specular Amount 0% |  Specular Amount 25% |  Specular Amount 50% |  Specular Amount 75% |  Specular Amount 100% |
Fresnel: At glancing angles (those perpendicular to the camera), reflectance values increase. The fresnel setting realistically increases the specular amount at these glancing angles producing a physically correct surface.
Specular Color: The 'Specular Color' function defines an RGB value that tints the specular highlight.
 Specular Color |  Specular Color |  Specular Color |  Specular Color |  Specular Color |
Roughness: Most surfaces are very different from each other --a rubber ball, a plastic cup, a terra cotta brick. These are all effectively smooth, but on a microscopic scale their surfaces are very different; having a direct affect on the way light reflects off of each one. The roughness setting simulates these microscopic differences making surfaces appear more dull or rough, or shiny and smooth. The 'Roughness' setting affects both the Specular highlight as well as ray traced and environmental reflections (reflection roughness only occurs when the Blurry Reflection option is active). Increasing this value will widen the reflection, creating a much broader specular highlight. When used with Blurry Reflections, a very high value will yield a very distorted reflection. In this case the number of Reflection Rays will most likely need to be increased to reduce graininess.
 Roughness 0% |  Roughness 25% |  Roughness 50% |  Roughness 75% |  Roughness 100% |
Anisotropy: Millions of microscopic scratches on a surface will distort highlights and reflections over their surface parallel to the directions of the scratches. The 'Anisotropy' value affects the highlights, simulating this effect. Anisotropy is controlled by a UV map or further controlled by a texture maps when the layers effect is set to the Anisotropy Direction. It can be caused by many man-made processes, such as machining metal and also appears in textiles where shiny threads spread the highlight over a surface.
 Anisotropy 0% |  Anisotropy 25% |  Anisotropy 50% |  Anisotropy 75% |  Anisotropy 100% |
UV Map: The UV map selector allows the user to choose which map will determine the anisotropic direction. The 'U" direction (horizontal) defines the direction of the virtual scratches.
Match Specular: This toggle option, when enabled, will match the 'Reflection Amount' and 'Fresnel' values to the like settings under Specular Amount. A specular highlight is simply the reflection generated by MODO's direct light sources, so naturally, to be correct, both would need identical values. With this checkbox, users will only need to adjust the values once. Additionally, this option takes into account any Texture layers with an effect defined as 'Specular Amount'/'Specular Color'. Users should note that when this option is enabled, all reflective shading is derived from the Specular channel so texture layers defined as 'Reflection Amount'/'Reflection Color' will be ignored.
Reflection Amount: The 'Reflection Amount' simply determines how reflective a surface is. At 100% the surface is effectively a perfect mirror whereas lower values will create a more muted reflection effect. Reflection is an additive effect, so reducing the diffuse amount is usually necessary to avoid overly bright surfaces. A surface is said to be 'physically correct' when Reflection amount and Diffuse Amount together equal 100%. Conserve energy will do this automatically and is enabled in the examples below..
 Reflection Amount 0% |  Reflection Amount 25% |  Reflection Amount 50% |  Reflection Amount 75% |  Reflection Amount 100% |
Fresnel: At glancing angles (those perpendicular to the camera), reflectance values increase. The fresnel (pronounced fra-nell) setting realistically increases the reflection amount at these glancing angles producing a physically correct surface.
 Fresnel 0% |  Fresnel 25% |  Fresnel 50% |  Fresnel 75% |  Fresnel 100% |
Reflection Color: The Reflection Color determines the tint on reflected light. By default the Color is white which reflects light without tint so that at 100% Reflection value, anything reflected in the surface would appear as if you were seeing it in a mirror. Setting the Reflection to something other than white will tint all reflected elements with that color.
 Reflection Color |  Reflection Color |  Reflection Color |  Reflection Color | Reflection Color |
Reflection Type: The Reflection type popup allows the user to choose between 'Full Scene' reflection evaluation or 'Environment' only. This setting is effectively switching between ray traced reflections and an environment map technique. The Full Scene option will be more accurate at the expense of greater render times. Environment will utilize only the settings in the 'Environment' item.
Blurry Reflection: When activated this feature will create a blurred reflection with the blur intensity being driven by the Roughness setting. It is important to understand that blurry reflections cause multiple reflection rays to be evaluated, each ray will be perturbed from the actual surface normal for every pixel. The higher the Roughness value the more reflection rays will be required to reduce noise in the reflection. If you consider that when the roughness value is increased the angle of each ray also increases you can imagine that the resulting sample from each ray can be quite different from one another. As such a higher number of rays is required to get an accurate average sample.
 Roughness 0% |  Roughness 25% |  Roughness 50% |  Roughness 75% |  Roughness 100% |
Reflection Rays: This value us only active when using Blurry Reflections. Increasing the Reflection Rays amount will improve the accuracy of the blurred reflection and reduce "grain" at the expense of computation time. Typically larger Roughness settings will require larger Reflection Ray settings as a wide spread of blur will need more samples to be accurate. If render times are a concern you can decrease the Roughness value rather than simply increasing the number of rays.
Clearcoat Amount: The 'Clearcoat' setting allows the user to easily add an additional unblurred and untinted reflective layer to a surface, simplifying the simulation of multiple layers of paint, especially automotive. Many metallic colors spread a wide colored highlight over the surface yet still exhibit a smooth reflective layer as a result of an additional transparent layer called a 'Clearcoat'. A setting of 0% effectively turns the clearcoat function off, increasing values add the reflective effect. Chief Scientist Allen Hastings says that in most cases that use Clearcoat, you'll just want to leave this setting at 100%.
 Clearcoat Amount 0% |  Clearcoat Amount 25% |  Clearcoat Amount 50% |  Clearcoat Amount 75% |  Clearcoat Amount 100% |
Surface Normal--
Bump Amplitude: Bump maps are a means of creating high frequency details on a surface that would be difficult, if not impossible to model. Bump mapping itself is a technique that modifies a rays direction when shading a surface giving the illusion that a surface has more detail than it actually does. The Bump Amplitude value allows a single control per material for modifying the amount of bump on a surface defined as a measurement. The size defined is relative to the surfaces actual size. The actual bump details come from the texture layer(s) driving the effect and the Bump Amplitude setting acts as a multiplier to create the final result. Please reference the 'Shader Tree' page of the documentation for information on adding layers and setting their effect.
 Bump Amplitude 0mm |  Bump Amplitude 2.5mm |  Bump Amplitude 5mm |  Bump Amplitude 7.5mm |  Bump Amplitude 10mm |
Displacement Distance: Similar to Bump maps, Displacement is a means to add detail to a surface that would be difficult, if not impossible to model otherwise. The maps themselves can be generated in MODO using the sculpting toolset, or in an external application such as ZBrush™ or Mudbox™; even procedural textures are useful as Displacement sources. The 'Displacement Distance' setting determines the maximum range vertices can be created or moved away from the original mesh surface during micro-polygon tessellation. With a value of 2 cm, no vertex can be displaced more than 2 cm away from the original surface. Depending on the mesh's scale, this value may need to be increased significantly. Further, when textures are applied to the displacement channel, should the combined texture value become greater than 100%, the resulting surface will appear to be clipped.
The maximum displacement distance is different from other material parameters because the renderer needs to know it way in advance, before any textures are evaluated. At the start of rendering, all surfaces are just empty bounding boxes. The vertices and polygons of a particular surface are only created in the geometry cache when a ray pierces the bounding box of the surface. For displaced surfaces, these bounding boxes must be "padded" with the maximum displacement distance in order to avoid holes, since displacement can cause geometry that would normally appear in a later bucket to show up in an earlier one. For this reason, the actual distance a vertex moves can never exceed the displacement distance, therefore texture values outside the range of -100% to 100% are always clipped.
Smoothing: Smoothing is a shading technique to give the illusion that geometry has more detail than it actually does. Without smoothing the geometric faces would appear faceted or flat. The smoothing amount is set as a percentage rather than a simple toggle so that you have the flexibility to "fade" in the smoothing amount or even drive it above 100% or below 0% to create interesting effects. At values over 100% the smoothing effect will result in "pillowing" around each polygon.
 Smoothing 0% |  Smoothing 25% |  Smoothing 50% |  Smoothing 75% |  Smoothing 100% |
Smoothing Angle: The Smoothing Angle determines which faces should receive smoothing. The smoothing angle sets a maximum angle tolerance between two polygons based on their normals. If the angle between the polygons is greater than the smoothing angle no smoothing will occur. This is useful so that hard edges, such as cubes, are not smoothed across. The default value of 40° is a good general case value.
Double Sided: The Double Sided toggle enables shading to occur from both sides of a polygon regardless of the normal direction. By default this value is off so that polygons that do not face the camera seem invisible as they only have one side. It should be noted that in some cases double sided polygons can cause render errors with ray tracing of shadows and other effects. The Double Sided flag should be used sparingly and never to correct poorly modeled meshes.
Rounded Edge Width: The 'Rounded Edge Width' option adjusts the rendered result of surface normals at a polygons edge to blend them with adjoining polygon normals, giving the impression of a small rounded edge between the two intersecting faces. To explain it more simply it shades polygons edges at render time to look as if a small rounded bevel has been applied, to what normally would be a sharp intersection. Users can define an Edge Width to determine the amount or 'roundness' but keep in mind it is merely a shading trick and wont round the edges of the actual geometry, nor change the objects silhouette in the rendered image, so it is best to keep set the length to just a few pixels in width in the final rendered image.
 Edge Width 0mm |  Edge Width 1mm |  Edge Width 2mm |  Edge Width 4mm |  Edge Width 8mm |
Round Same Surface Only: When this option is enabled, edge rounding will be constrained to the surface within the same item layer. When disabled, rounded edges will be applied to the surface regardless of item layer.
Material TransLayer--
Enable: Toggles the effect of the layer on and off, duplicating the functionality of toggling visibility in the Shader Tree. When un-checked (disabled), the layer has no effect on the shading of the scene. However, disabled layers are saved with the scene and are persistent across MODO sessions.
Invert: Inverts the RGB values for the layer producing a negative effect.
Blend Mode: Affects blending between different layers of the same effect type, allowing user the ability to stack several layers for different effects. For more on blending, please reference the 'Blend Modes' page of the documentation.
Opacity: Changes the transparency of the current layer. Reducing this values will increasingly reveal lower layers in the shader tree if present, or dim the effect of the layer itself on the surface.
Transparency--
Transparency Amount: The 'Transparency Amount' controls how transparent or opaque a surface is. 0% is completely opaque and disables the setting altogether, settings above 0% gradually increase how transparent the surface is ramping toward 100% which is completely transparent. -- (image examples below)
Transparency Color: The 'Transparent Color' determines what color a ray is tinted as they penetrate the transparent surface. Since many transparent materials such as glass should have no diffuse amount whatsoever, the transparent color is used for tinting the material. At the default, pure white, a material that is 100% transparent will become completely invisible unless there are reflections and/or specular highlights. By changing the transparency color, the material will now appear (as MODO will simply tint whatever the camera sees behind the surface). -- (image examples below)
Absorption Distance: Colored transparent surfaces don't often exhibit even coloration. Thin areas will appear colorless while thicker areas will tint with color. The 'Absorption Distance' controls this effect, determining how far a ray must travel to get 100% of the Transparency Color. The falloff is determined by Beer's Law, just as in the real world. -- (image examples below)
Refractive Index: The Refractive Index determines how far the a light ray is bent when it travels through a material. The higher the value the more distorted the refracted items will become. For instance, a value of 1.0 is equivalent to light traveling through a vacuum and will not bend the rays at all. Increasing the value to 1.333 would approximate the amount of distortion that occurs when light travels through water. This setting requires the surface have some amount of transparency active. -- (image examples below)
--REFRACTIVE INDEX TABLE--
 Trans. Amount 0% |  Trans. Amount 25% |  Trans. Amount 50% |  Trans. Amount 75% |  Trans. Amount 100% |
 Transparency Color |  Transparency Color |  Transparency Color |  Transparency Color |  Transparency Color |
 Absorption Dist. 100mm |  Absorption Dist. 200mm |  Absorption Dist. 300mm |  Absorption Dist. 400mm |  Absorption Dist. 500mm |
 Refractive Index 1.0 |  Refractive Index 1.5 |  Refractive Index 2.0 |  Refractive Index 2.5 |  Refractive Index 3.0 |
Dispersion: Dispersion is the difference of Refractive Index between various wavelengths of lights. Pure white light in the real world contains all colors of the spectrum, as it passes through solid objects, the refraction of different wavelengths varies creating a rainbow effect. You've likely witnessed this when shining a bright light through a prism. This effect in gemstones is usually referred to as 'fire'. In MODO, it is calculated as the difference between a high refractive index (at the violet end of the spectrum) and low refractive index (at the red end of the spectrum). A typical dispersion value for glass would be around .02 whereas diamond would be .044. Negative dispersion values will invert to the usual curve.
 Dispersion 0 |  Dispersion 0.025 |  Dispersion 0.05 |  Dispersion 0.075 |  Dispersion 0.1 |
Refraction Roughness: Some transparent surfaces are better described as translucent or cloudy -- light passes through the surface, but is diffused in such a way as to make opposing items blurry or even completely indistinguishable. Frosted glass exhibits this effect, items close to the surface are clear, but as they recede from view, edges and details soften increasingly. The 'Refraction Roughness' calculates this effect by firing a number of jittered rays for each refraction ray and averages the result. A value of 0% disables the effect, values above 0% increase the blurriness of items viewed through the surface.
 Ref. Roughness 0% |  Ref. Roughness 5% |  Ref. Roughness 10% |  Ref. Roughness 15% |  Ref. Roughness 20% |
Refraction Rays:The 'Refraction Rays' setting specifies the number of rays MODO uses to calculate the Refraction Roughness setting. As the Refraction Roughness amount grows, you will need to increase the number of rays necessary to produce a smooth effect, though at the expense of longer render times.
Dissolve Amount: The 'Dissolve Amount' will allow one to fade an object completely from view. A setting of 100% would make the surface completely invisible. The Dissolve amount is different from transparency as it is a convenient way to fade all aspects of a surface simultaneously.
 Dissolve Amount 0% |  Dissolve Amount 25% |  Dissolve Amount 50% |  Dissolve Amount 75% |  Dissolve Amount 100% |
Subsurface Scattering--
Subsurface scattering is the effect of light bouncing around inside a surface and "tinting" prior to exiting. This is often most obvious in materials like marble but is essential to creating realistic wax or fleshy materials. Subsurface scattering also helps simulated liquids such as milk to appear more natural. In humans "SSS" is most often witnessed when thin areas on the ears seem to turn red from back light as the light is being tinted by the tissues underneath the skin itself.
Subsurface Amount: Subsurface scattering contributes to the diffuse shading of a material. The 'Subsurface Amount' is a percentage value that determines the contribution of diffuse shading made by subsurface scattering. It is a good idea to keep this in mind in order to balance the percentages between Diffuse Color and Subsurface Amount depending on which effect you prefer for final shading. Also, combining high Diffuse Amounts and high Subsurface Amounts can yield unnatural shading results. Hey, if that's what you're into, there is nothing wrong with that.
 Subsurface Amount 0% |  Subsurface Amount 25% |  Subsurface Amount 50% |  Subsurface Amount 75% |  Subsurface Amount 100% |
Subsurface Color: The Subsurface Color is the color value that will be used to tint the light as it is attenuated through the material. This setting and the Scattering Distance work together to determine how far the light must travel to be tinted.
 Subsurface Color |  Subsurface Color |  Subsurface Color |  Subsurface Color |  Subsurface Color |
Scattering Distance: The 'Scattering Distance' setting determines how far light must travel through the surface prior to exiting in order to be fully tinted by the Subsurface Color. If the light travels beyond the scattering distance it will be further attenuated according to the original Subsurface color.
Maximum Depth: The 'Maximum Depth' option is a fast way to approximates an opaque solid core within the Subsurface layer (example - a bone inside a finger) by clipping any scattering samples that reach beyond 'Maximum Depth' value specified. Be aware that this may lead to a slightly darker scattering because the clipped samples exclusion from the solution, but an increase in the number of total 'Samples' can help to reduce or eliminate this effect. A setting of zero disabled the option.
Front Weighting: The 'Front Weighting' value sets a bias for the SSS rays. At 50%, SSS rays will scatter evenly forward and backward though a surface. Higher values bias the scattered rays toward the light source that emitted them creating a more waxy/flat look to SSS, while values lower than 50% bias the scattered rays away from the light source darkening the overall SSS effect.
 Front Weighting 0% |  Front Weighting 25% |  Front Weighting 50% |  Front Weighting 75% |  Front Weighting 100% |
Samples: The Subsurface 'Samples' controls the quality of the subsurface shading. Increasing this value will improve the quality of the effect at the expense of render speed. The default setting is 64.
Same Surface Only: When the 'Same Surface Only' toggle is enabled, MODO's subsurface scattering works as it previously did, by limiting the SSS sample cache values to affect the shading to a single surface. This was to prevent certain artifacts that would occur with very thin surfaces or intersections with non-SSS surfaces. This optimization however limits adjoining SSS surfaces from sharing values resulting in a slight dark border between them; in which case, 'Same Surface Only' should be disabled.
Luminosity--
Luminous Intensity:The Luminous Intensity is multiplier that drives the brightness of the Luminous color as it is emitted from the surface. This is different than Diffuse Amount in that Diffuse requires some amount of light to hit the surface whereas Luminous comes from the surface itself. It is accurate to think of Luminous surfaces as light sources - particularly when using Global Illumination. The Luminous Intensity is multiplied to the Luminous Color. By default the Value is zero which results in the Luminous color control being disabled and as such it is not calculated.
 Luminous Intensity 0 |  Luminous Intensity 0.25 |  Luminous Intensity 0.5 |  Luminous Intensity 0.75 |  Luminous Intensity 1 |
Luminous Color: The 'Luminous Color' setting allows the user to specify a color value for light emitted from a surface as specified by the 'Luminous Intensity' setting.
 Luminous Color |  Luminous Color |  Luminous Color |  Luminous Color |  Luminous Color |
Material Rays
Ray Tracing--
Exit Color: Originally when a series of refraction rays hit the maximum refraction depth, MODO would return black as the final value, so in scenes with low refraction depth values would exhibit lots of dark areas. The 'Exit Color' allows you to now specify the color MODO returns once it has reached its ray threshold. The color is still attenuated with the initial ray bounces --colors, absorption and such, however this setting can reduce a lot of the dark areas present with lower refraction depth values. In the first example below, there is a good amount of black revealed because of the low refraction depth. In the second image, the exit color was changed to a medium gray, simulating the background color resulting in a more accurate representation. Finally, the last image changes the exit color to red make obvious the effects of the exit color setting.
 Exit Color (Default) |  Exit Color Gray |  Exit Color Red |
Use Vertex Irradiance Cache: The 'Use Vertex Irradiance Cache' option can be used to increase performance of Irradiance Cache global illumination rendering for certain kinds of geometry, like characters and fur. This is because cached values can be easily referenced speeding up the evaluation of subsurface scattering, fur, and G.I in general. When enabled on a surface, Irradiance Cache values are calculated at each vertex position (at the subdivision level) and interpolated in-between producing the shaded result. Note that the cache size is directly related to the subdivision vertex density, more polygons equals more IC values.
Enable Surface Clipping: Enabled by default, Surface Clipping refers to the removal of part of the scene as defined by the 'Clipping Plane' settings of the Camera Item. Users can define a distance where all (or selected) surfaces will be clipped, removing them from the rendered image while leaving the scene geometry intact. In order for Surface Clipping to work, it must first be enabled in the Camera Item, under the 'Clipping' attributes. There users can define the distance value as well, determining the distance away from the camera where the scene will clip in the rendered image. Users can disable the clipping effect on a per-material basis by disabling this option. Users should note that a similar effect can also be obtained through the use of 'Render Booleans' that is not camera view dependent.
Matte Clipping: 'Matte Clipping' provides users a means to colorize interior areas of clipped geometry producing a filled area of color, the color being determined by the 'Matte Color' value.
Matte Color: Determines the color of clipped interior areas when Clipping is enabled in both the Material clipping attributes and in the Camera Item.
Volumetric--
When light shines on particular matter suspended in the air, such as water vapor, smoke, dust or even pollution, the particles become visible, this is known in computer graphics as a volumetric effect. Two things then happen to the light; part of it is bounced back in all directions (this is called scattering) and part of it is absorbed (this is called absorption). The density parameter is the particle density of the volume, so the higher the density the more apparent particles there will be. When the density is increased, the scattering and the absorption will increase as well, so your volume becomes both more opaque and more luminous. However, when density is increased, the volume becomes more opaque, and the light scattered inside is more attenuated so the net result in terms of overall luminosity is hard to predict, the final result depends on the balance of scattering vs absorption vs density. In simple terms one can say that scattering is similar to diffuse shading and absorption is inversely similar to luminosity (more light reflected back makes the volume appear luminous). This is however more subtle than that since the overall luminosity also depends on how much absorption happens inside the volume.
The following settings only apply to the 'Volume' item and otherwise will have no affect on the surface. Likewise, the other surfacing attributes, such as 'Diffuse Color' and 'Reflection Amount' will have no affect on a Volumetric item. The Volume item also contains similar options that act as multiplies of the below values, allowing users some additional tweaking options.
Scattering Amount: Scattering defines the amount of light that is reflected from the volume. This can also be described as how luminous the volume is, where a cloud is puffy and white, it is because it reflects back a lot of the light it receives (also absorbing very little). Conversely, a dense smoke cloud from an oil fire would reflect back very little light looking very dark and ominous. A value of 0% would reflect back no light received from the source, up toward 100% (the default value) where the volume reflects back all of the light it receives.
 Scattering Amt. 0% |  Scattering Amt. 25% |  Scattering Amt. 50% |  Scattering Amt. 75% |  Scattering Amt. 100% |
Scattering Color: The 'Scattering Color' represents the apparent color of the volume, representing the light that is reflected from the particulate matter.
 Scattering Color |  Scattering Color |  Scattering Color |  Scattering Color |  Scattering Color |
Absorption Amount: The 'Absorption Amount' determines how much light is absorbed into the particular matter. If low amounts of light are absorbed, then more light is reflected back producing a brighter, more luminous volume, where when more light is absorbed, then the volume will appear darker and more powdery/dust like (A value of '0' produces no results, so the very small value 0.01 was substituted).
 Absorption Amt. 0.01% |  Absorption Amt. 25% |  Absorption Amt. 50% |  Absorption Amt. 75% |  Absorption Amt. 100% |
Absorption Color: The 'Absorption Color' determines the color that is absorbed into the volume (which produces an inverted hue to what is applied).
 Absorption Color |  Absorption Color |  Absorption Color |  Absorption Color |  Absorption Color |
Density: The 'Density' value determines the thickness of the volume, controlling the apparent amount of particular matter that is visible.
 Density 100% |  Density 75% |  Density 50% |  Density 25% |  Density 0% |
