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  Material types and their settings > Advanced
  Advanced
  The advanced material is the most versatile of all KeyShot material types. There are more parameters in this material than any other. With the variety of parameters, materials such as metals, plastic, transparent or cloudy plastics, glass, diffuse and leathers can all be created from this single material type. Material types that cannot be created are translucent materials and metallic paints.
 
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Color Specular Bump Opacity
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  Diffuse  
  This can be thought of as the overall color of the material. Transparent materials will have little or no diffuse. Metals will have no diffuse with all the color derived from the specular.

To fully understand this parameter see the section on diffuse.
 
  Specular  
  This is the color and intensity of the reflection of light sources within the scene. Black will be 0 intensity and the material will not be reflective. White will be 100% intensity and will be completely reflective.

If a metal material is being created, this is where the color is set. If a plastic material is being created, the specular color should be white or grey to reduce reflectivity. Plastics will not have color in the specular.

To fully understand this parameter see the section on specular.
 
  Specular transmission  
  This can be thought of as the transparency of the material. Black will be 100% opaque and white will be 100% transparent.

If a transparent glass or plastic is being created, the diffuse should be black with all the color derived from this parameter. Transparent glasses or plastics should also have the specular set to white. If a cloudy plastic is desired, the diffuse can be set to a very dark version of the color set here.
 
  Diffuse transmission  
  This will cause additional light scattering across the surface of the material which can simulate a translucent effect. It will increase render time, so if it is not needed the recommendation is to leave it at black.
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  Ambient Roughness
  This will control the color of self shadowing on the material in areas that are not receiving direct light. It can produce unrealistic looks, so it is recommended to keep this set to black unless it is needed. This will add microscopic levels of imperfections to the surface of the material when the values are increased. When set to 0, a material will appear perfectly smooth and polished. When the value is increased the material will appear more rough as light is diffused across the surface.
 
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  Roughness transmission Refraction index
 
This will control the roughness of the refractions. The main difference between this parameter and roughness is that the roughness is on the internal portion of the material. This can be used to create a frosted look while still maintaining a shiny surface. The material needs to have some transparency through the specular transmission to see any affect.  
This will control the level of refraction on the material.
 
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  Fresnel (pronounced frah-nel) Glossy samples
 
This will control the intensity of the reflections that are perpendicular to the camera. In the real world, materials are more reflective around the edges of objects than they are on areas of objects that are directly facing the viewer or camera. It is enabled by default because in it is the accurate setting. Different materials have different fresnel falloff.  
This will control the accuracy of glossy (rough) reflections.
 
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