This page gives some basic details about the Shadow Render Element and how it is used in compositing.
The Shadow Render Element is a color image that works as a reverse mask for shadows and can be used to lighten, darken or tint shadows. Shadows can be lightened in the composite by adding this pass, or darkened by subtracting this render pass from the final composite.
Note : Specific objects can be excluded from this Render Element by disabling the Generate Render Elements option in the VRayObjectProperties node for the selected object(s).
||Render Settings window|| > Render Elements tab > Shadow
The parameters for this render element appear in the Attribute Editor under Extra V-Ray Attributes.
Enabled – When enabled, the render element appears in the V-Ray Virtual Frame Buffer.
Deep output – Specifies whether to include this render element in deep images.
Filename suffix – The text added to the end of the rendered file, when saved as a separate file (e.g. myrender.shadow.vrimg).
Denoise – Enables the render element's denoising, provided the Denoiser render element is present.
The Shadow Render Element is useful for changing the appearance of shadowed areas in a compositing or image editing application. Below are examples of possible uses.
Shadow Render Element
Original Beauty Composite
Contrast added to the Shadows Render Element
Underlying Compositing Equation
The vrayRE_Shadow pass can be both added and subtracted with the final beauty comp at a composite level without rerendering.
Shadows can be color-corrected using the vrayRE_Shadow element.