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The glossiness parameter controls how much the reflections are blurry. The samples parameter controls the noise level of the glossy reflections. Differences in the Glossiness setting can be seen below.
Glossiness at 0.01
Glossiness at 0.05
Glossiness at 0.99
Fresnel Reflection
Fresnel support is essential as it is the way real surfaces interact with the light. The strength of the reflection generally depends on the viewing angle (the angle between the observer and the surface normal).
Fresnel reflection OFF
Fresnel reflection ON
Specular Highlights
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