This page gives some basic details about the Raw Refraction Render Element and how it is used in compositing.
Overview
The Raw Refraction Render Element is a color image that stores refraction information calculated from materials' refraction values in the scene. Surfaces with no refraction values set in their materials will contain no information in the render element and therefore will render as black.
In comparison, the Refraction Filter is a render element that indicates varying degrees of refraction in the scene through brightness values in the image. Multiplying these two render elements together produces the Refraction Render Element.
To properly calculate the Raw Refraction Render Element, the Refraction Render Element must also be added to the list of render elements being calculated during the rendering process to properly determine all the refraction information in the scene.
UI Path
||out Network|| > V-Ray Render Elements node > V-Ray > Render Channel > Color Channel > Type > Raw Refraction
Attributes
The parameters for this render element appear in the V-Ray RenderChannelColor render channels node.
Denoise – Enables the render element's denoising, provided the Denoiser render element is present.
Consider for Anti-Aliasing – When enabled, anti-aliasing will be used where possible.
Filtering – Applies the image filter to this channel. Image filter settings are in the Image Sampler tab of the Sampler tab of the V-Ray Renderer node.
Color Mapping – When enabled, the Color Mapping options in the render settings will be applied to the current render channel.
Derive Raw Channels – Generates data in the raw channels by combining the respective color and the filter color channels.
VFB Color Corrections – Applies the post render color adjustments made from the VFB.
This render element is not supported with V-Ray GPU rendering.
Common Uses
The Raw Refraction Render Element is useful for changing the appearance of refractive elements after rendering in a compositing or image editing application. Below are examples of possible uses.
Raw Refraction Render Element with added contrast
Tinted Raw Refraction Render Element with added contrast
Refractions with more contrast
Tinted Refractions with more contrast
Underlying Compositing Equation
Raw Refraction x Refraction Filter = Refraction
Notes
- To properly calculate the refraction information in the Raw Refraction and Refraction Filter Render Elements, the Refraction Render Element must also be rendered at the same time, even if it's not going to be used in the compositing process. Doing so enables all the refraction information to be included in the rendering calculations.
- This render element is not supported with V-Ray GPU rendering.