Consider the following scenario: you created a visualization, rendered everything, but you're dissatisfied with the lighting results you got. It will take a significant amount of time to generate visuals from the beginning, but to leave lighting you applied earlier is not an option as well. So, what to do? The answer is simple – post-production. Then you render the visualization at the same time you generate Render Items — hidden elements that you specified before starting to render. These components are used to deconstruct visuals into component pieces, such as diffuse color, reflections, shadows, mattes, and so on. These components give you control over your image, allow you to edit separate parts of your visualization during and after rendering. V-Ray render elements are divided into four major groups: Beauty Render Elements, Matte Render Elements, Geometry Render Elements, Utility Render Elements. In this blog post, we'll discuss Beauty Render Elements and how they're used in post-production process.
Beauty Render Elements
The Beauty Render Element (or just Beauty pass) is V-Ray's generated final image and is usually the primary export when rendering a scene. Beauty pass includes render components such as lighting, global illumination, reflection, refraction, specular, etc., and can be recreated manually by bringing the right components together and making small adjustments to them. The components of Beauty Render and how they might be used in the post-production process are discussed below.
V-Ray lighting Render Element stores direct lighting information from the scene's lights, along with the way materials were illuminated by the lighting. This render element allows to brighten, dim, or tint the direct illumination of the rendered image, which could be incredibly beneficial in post-production process.
The V-Ray Global Illumination Render Element is a color image that stores indirect lighting information coming from reflected diffuse light in a scene (without direct light and reflection contributions) when Indirect Illumination is enabled. This element may be used directly in Back to Beauty compositing and adjusted for brightness and color to control the final image easily.
The Global Illumination Render Element is useful for changing the appearance of Indirect lighting after rending in a compositing or image editing software.
V-Ray Reflection Render Element stores reflection data calculated from the scene's materials' reflection values. This render element may be used to modify the reflectivity of elements (the reflection values), making them more or less reflective even after the rendering process.
The Refraction Render Element’s information is calculated from materials that refract objects behind them in the camera's perspective, such as glass or water. This render element is one of the main Beauty Elements that changes the appearance of refractive components in visualization during or after the rendering process by modifying brightness, color, and other parameters.
The Specular Render Element is an image that stores specular reflection data from the material's reflection value in the scene. Specular reflection is described as the single reflection of light from a surface, as contrary to diffuse reflection, which is reflected at multiple angles. The Specular Render Element is useful for changing the final image's specular appearance during compositing. During post-production, the Specular Render Element is useful for modifying the final image's specular appearance and is used to form the final image.
The Atmosphere Render Element stores only atmospheric or volumetric data such as fog or Aerial Perspective. During post-production process, this render element is useful for enhancing or color-correcting the atmospheric component of visualization.
The Background Render Element is primarily used for layering the Beauty element (or combined render elements) on top of the background image.
In our next blog post, we'll publish a teaching video about the light mix function and show how it's applied in the post-production process.