Tone Map Copernicus node

Applies a filmic tone mapping curve to compress a high dynamic range input into a displayable range.

On this page	Parameters Inputs Outputs
Since	21.0

Tone mapping converts from high dynamic range real-world luminances to low dynamic range display values. This makes images displayable on monitors. Tone mapping also simulates a particular film look. Film material has a response to light that enhances contrast and colors, represented as a characteristic curve.

A filmic tone mapping curve is subdivided into toe, shoulder, and linear sections for an image’s dark, bright, and midtones. Houdini provides common operators for filmic tone mapping and each operator applies a specific S-shaped tone mapping curve.

Parameters ¶

Signature

The layer type that the source accepts.

See Signatures for more information.

Operator

The filmic tone mapping operator to use.

Reinhard

Computes a global scale factor that preserves detail in low contrast areas, while compressing high luminances to a displayable range. This function ensures that the output approaches 1 as luminance increases, which prevents overexposure while preserving details in both shadows and highlights. This is a simple and fast function.

Ward

Yields a display with roughly the same contrast visibility as the actual scene. This uses a constant scale factor that, when applied to the calculated pixel values, makes the differences visible in only the real-world visible in only your display.

ACES Filmic

Applies an efficient approximation of the Academy Color Encoding System (ACES) tone mapping curve.

Hable Filmic

Applies a filmic tone mapping curve with cinematic highlight rolloff and contrast shaping.

Hable Filmic Updated

Uses piecewise power curves for improved artistic control over contrast, shoulder rolloff, and toe response. An enhanced version of Hable Filmic, this offers a more intuitive way to independently adjust the highlight and shadow curves.

Unreal

Unreal Engine’s filmic tonemapper implements the ACES standard while providing more controls on adjusting different parts of the S-curve.

Mask

The amount of the new value to mix in with the original value. Higher values mix in more of the new value. Lower values mix in less of the new value. You can also set the RGBA channels to which you apply the effects of this node.

The default value is 1, which means this node uses only the new value. See Mask for more information.

Toggle RGB

Turns the Red, Green, and Blue channels on and off.

Red

Applies this node’s effects to the Red channel.

Green

Applies this node’s effects to the Green channel.

Blue

Applies this node’s effects to the Blue channel.

Alpha

Applies this node’s effects to the Alpha channel.

Treat RGBA as Premultiplied

Treats RGBA as premultiplied, which multiplies the red, green, and blue channels by the alpha channel.

Exposure

The overall brightness of the image before the node applies tone mapping. Each unit increases brightness by one stop (doubling the light) and negative values darken the image.

Shoulder Strength

The strength of the curve at the shoulder section.

Lower values cause a more gradual falloff at high luminance. The curve bends downward earlier and compresses the highlights more aggressively, which mutes the highlights. Higher values make the curve compress the highlights less initially so the curve stays linear for longer and only flattens near the top, which lets bright areas stay brighter.