Node Reference Guide

This node reference guide contains a brief description of each node that appears in the Node list. It’s broken down into three sections:

Layer Nodes

The following nodes have multiple inputs and are used to combine two or more differently processed versions of the corrected image in different ways.

Add

Mathematically adds each pixel from the two input images together. Add operations are particularly well suited to creating aggressive glowing effects, because they tend to raise levels very quickly depending on the input images. Bear in mind that the best way of controlling which areas of the image are being affected when using an Add operation is to aggressively control the contrast of one of the input images. The darker an area is, the less effect it will have.

The order in which the inputs are connected does not matter. Add has two parameters:

  • Source 1 Bias: Controls how much of the Source 1 image is added to create the final result by multiplying the value in each channel by the specified value. Defaults to 0.5.
  • Source 2 Bias: Controls how much of the Source 2 image is added to create the final result by multiplying the value in each channel by the specified value. Defaults to 0.5.

Alpha Blend

This node blends (similar to the Blend node) the Source 2 input to the Source 1 input in all the areas where the Source 3 Alpha input image is white. Where the Alpha input image is black, only the Source 1 input is shown. The order in which the inputs are connected affects the output.

Blend

This node mixes two inputs together based on the Blend parameter. The order in which the inputs are connected does not matter. Blend has one parameter:

  • Blend: When set to 0, only Input 1 is output. When set to .5, Input 1 and Input 2 are blended together equally and output. When set to 1, only Input 2 is output.

Darken

Emphasizes the darkest parts of each input. Overlapping pixels from each image are compared, and the darkest pixel is preserved. Areas of white from either input image have no effect on the result. The order in which the inputs are connected does not matter.

Difference

The pixels from the image that’s connected to Source 1 are subtracted from the pixels from the image that’s connected to Source 2. Black pixels have a value of 0, so any color minus black results in no change to the image from Source 1. Since this is subtraction, the order in which the inputs are connected matters.

Interlace

The images connected to each input are interlaced. The Left input is for the Even field, and the Right input is for the Odd field. This node is used at the end of node trees that begin with Deinterlace nodes to process effects for projects using interlaced media.

Lighten

Lighten emphasizes the lightest parts of each input. Overlapping pixels from each image are compared, and the lightest pixel is preserved. The order in which the inputs are connected does not matter.

Multiply

The pixels from each input image are multiplied together. White pixels have a value of 1, so white multiplied with any other color results in no change to the other image. However, when black (0) is multiplied with any other color, the result is black.

When multiplying two images, the darkest parts of the images remain unaffected, while the lightest parts of the image are the most affected. This is useful for tinting operations, as well as for operations where you want to combine the darkest portions of two images.

RGB Merge

The three inputs are used to insert individual channels into the red, green, and blue color channels. You can split the three color channels apart using the RGB Split node, process each grayscale channel individually, and then reassemble them into a color image again with this node.

Effects Nodes

The following nodes have a single input and are used to apply a single correction or effect to an image.

B&W

Desaturates the image to produce a monochrome image consisting of only the Luma component. This is done using very specific math, adding together 0.299 of the red channel, 0.587 of the green channel, and 0.114 of the blue channel to arrive at the final monochrome result.

Bleach Bypass

Raises the contrast and desaturates the image. Simulates laboratory silver-retention processes used to raise image contrast in film by skipping the bleaching stage of film development, leaving exposed silver grains on the negative which boost contrast, increase grain, and reduce saturation.

Blur

Blurs the image. Blur has one parameter:

  • Spread: The amount of blur. Can be set to a value from 0 (no blur) to 40 (maximum blur).

Clamp

Two parameters clip the minimum and maximum values in the image. Clamp has two parameters:

  • Min: The minimum level in the image. Any levels below this value are set to this value.
  • Max: The maximum level in the image. Any levels above this value are set to this value.

Curve

A curve that affects image contrast similar to the Luma curve in the Primary In room. Selecting this node displays a curve control in the Parameters tab that works identically to those found in the Primary In room. Four buttons below let you choose which channel the curve operates upon:

  • Luma: Sets the curve to adjust the luma component of the image.
  • Red: Sets the curve to adjust the red color channel of the image.
  • Green: Sets the curve to adjust the green color channel of the image.
  • Blue: Sets the curve to adjust the blue color channel of the image.

Duotone

Desaturates the image, mapping the black and white points of the image to two user-customizable colors to create tinted images with dual tints from white to black. Duotone has two parameters:

  • Light Color: The color that the white point is mapped to.
  • Dark Color: The color that the black point is mapped to.

Edge Detector

A Convolution filter that boosts image contrast in such a way as to reduce the image to the darkest outlines that appear throughout. Edge Detector has three parameters:

  • B&W: Desaturates the resulting image. Useful when using this node to generate mattes.
  • Scale: Adjusts the white point. Lowering Scale helps increase contrast and crush midtone values to emphasize the outlines.
  • Bias: Adjusts overall contrast. Lowering Bias increases contrast, while raising it lowers contrast.

Exposure

Raises the highlights or crushes the shadows, depending on whether you raise or lower the Exposure parameter. This node has one parameter:

  • Exposure: Raising this parameter raises the highlights while keeping the black point pinned. Setting this parameter to 0 results in no change. Lowering this parameter scales the image levels down, crushing the shadows while lowering the highlights by a less severe amount.

Film Grain

Adds noise to the darker portions of an image to simulate film grain or video noise due to underexposure. Highlights in the image are unaffected. This node is useful if you have to match a clean, well-exposed insert shot into a scene that’s noisy due to underexposure. Also useful for creating a distressed film look. This node has three parameters:

  • Grain Intensity: Makes the noise more visible by raising its contrast ratio (inserting both light and dark pixels of noise) as well as the saturation of the noise.
  • Grain Size: Increases the size of each “grain” of noise that’s added. Keep in mind that the size of the film grain is relative to the resolution of your project. Film grain of a particular size applied to a standard definition shot will appear “grainier” than the same-sized grain applied to a high definition shot.
  • Monochrome: Turning this button on results in the creation of monochrome, or grayscale, noise, with no color.

Film Look

An “all-in-one” film look node. Combines the Film Grain operation described above with an “s-curve” exposure adjustment that slightly crushes the shadows and boosts the highlights. Contrast in the midtones is stretched, but the distribution of the midtones remains centered, so there’s no overall lightening or darkening. This node has three parameters:

  • Grain Intensity: Makes the noise more visible by raising its contrast ratio (inserting both light and dark pixels of noise) as well as the saturation of the noise.
  • Grain Size: Increases the size of each “grain” of noise that’s added. Keep in mind that the size of the film grain is relative to the resolution of your project. Film grain of a particular size applied to a standard definition shot will appear “grainier” than the same-sized grain applied to a high definition shot.
  • Contrast: Makes an “s-curve” adjustment to contrast, which crushes the shadows and boosts the highlights, while leaving the midtones centered. A value of 0 preserves the original contrast of the corrected image, while a value of 1 is the maximum contrast expansion that is possible with this node.

Gain

Adjusts contrast by raising or lowering the white point of the image while leaving the black point pinned in place, and scaling the midtones between the new white point and the black point. This node has four parameters:

  • Gain: Adjusts the red, green, and blue channels simultaneously, for an overall change to image highlights and midtones.
  • Red Gain: Adjusts the red channel only, enabling color correction based on a white point adjustment for that channel.
  • Green Gain: Adjusts the green channel only, enabling color correction based on a white point adjustment for that channel.
  • Blue Gain: Adjusts the blue channel only, enabling color correction based on a white point adjustment for that channel.

Gamma

Makes a standard gamma adjustment, which makes a nonlinear adjustment to raise or lower the distribution of midtones of the image while leaving the black and white points pinned in place. This is a power function, (f(x) = xa). This node has four parameters:

  • Gamma: Adjusts the red, green, and blue channels simultaneously, for an overall change to image midtones.
  • Red Gamma: Adjusts the red channel only, enabling color correction based on a gamma adjustment for that channel.
  • Green Gamma: Adjusts the green channel only, enabling color correction based on a gamma adjustment for that channel.
  • Blue Gamma: Adjusts the blue channel only, enabling color correction based on a gamma adjustment for that channel.

Grain Reduction

Reduces grain and noise in an image by averaging adjacent pixels in that frame according to the values specified in the Master, Red, Green, and Blue Scale parameters. Edge detection can be used to preserve sharpness in areas of high-contrast detail via the Edge Retention parameter, and a sharpening operation can be applied after grain reduction to boost overall detail. Because some shots have noise that’s more apparent in specific color channels, you can make independent adjustments to each channel. This node has six parameters:

  • Master Scale: Averages the adjacent pixels of every color channel in the image to reduce grain and noise, at the expense of a certain amount of image softness.
  • Red Scale: Selectively averages pixels in the red channel.
  • Green Scale: Selectively averages pixels in the green channel.
  • Blue Scale: Selectively averages pixels in the blue channel.
  • Edge Retention: Uses edge detection to isolate areas of high-contrast detail in the image (such as hair, eyes, and lips in an actor’s close-up), and excludes those areas of the image from the Grain Reduction operation to preserve the most valuable image detail from softening. Higher values preserve more of the original image in these areas.
  • Post Sharpening: Applies a Sharpening Convolution filter after the Grain Reduction operation to try and restore some lost detail once the grain has been softened. Use this parameter sparingly—if you set this too high, you’ll end up reintroducing the grain you’re trying to reduce.

Hue

Rotates the hue of every pixel in the entire image. This node has one parameter:

  • Shift: The amount by which you want to shift the hue. This is not done in degrees, as is represented in the Vectorscope. Instead, you use a value from –1 to 1, where –1, 0, and 1 place the hue at the original values.

Invert

Inverts the image. Useful for creating “positives” from the image negative. Also useful for reversing a grayscale image that you’re using as a matte with the Alpha Blend node, to reverse the portions of the matte that will be solid and transparent.

Lift

Lift uniformly lightens or darkens the entire image, altering the shadows, midtones, and highlights by the same amount. This node has four parameters:

  • Lift: Adjusts the red, green, and blue channels simultaneously, for an overall change to image brightness.
  • Red Lift: Adjusts the red channel only, enabling color correction based on a lift adjustment for that channel.
  • Green Lift: Adjusts the green channel only, enabling color correction based on a lift adjustment for that channel.
  • Blue Lift: Adjusts the blue channel only, enabling color correction based on a lift adjustment for that channel.

Maximum

Averages adjacent pixels together (how many is based on the Brush Size parameter) to produce a single, larger pixel based on the brightest value in that pixel group. Larger values result in flattened, almost watercolor-like versions of the image. This node is also useful for expanding the white areas and smoothing out grayscale images that you’re using as mattes. This node has one parameter:

  • Brush Size: Defines how many pixels are averaged into a single, larger pixel. Extremely large values result in progressively larger, overlapping square pixels of uniform color, emphasizing lighter pastel-like tones in the image.

Minimum

Averages adjacent pixels together (how many is based on the Brush Size parameter) to produce a single, larger pixel based on the darkest value in that pixel group. Larger values result in flattened, darkened versions of the image. This node is also useful for expanding the black areas and smoothing out grayscale images that you’re using as mattes. This node has one parameter:

  • Brush Size: Defines how many pixels are averaged into a single, larger pixel. Extremely large values result in progressively larger, overlapping square pixels of uniform color, emphasizing darker, muddier tones in the image.

Printer Lights

Provides Red, Green, and Blue parameters for color correction that work identically to the printer points controls in the Advanced tab of the Primary In room. For more information, see Printer Points Controls.

Saturation

Raises or lowers overall image saturation, making the image more or less colorful. If you use the Saturation node to completely desaturate an image, all three color channels are blended together equally to create the final monochrome result, which looks different then if you had used the B&W node. This node has one parameter:

  • Saturation: The default value of 1 produces no change. 0 is a completely desaturated image, while the maximum value of 10 produces an excessively saturated, hyper-stylized version of the image.

Scale RGB

Expands or contracts the overall contrast ratio of a shot, from the black point to the white point, centering the midpoint of this operation at a percentage of image tonality that you specify. This node has two parameters:

  • Scale: The amount by which to expand or contract the overall contrast ratio in the shot. This is a multiplicative operation, so a value of 1 produces no change, while larger values increase the contrast ratio, and smaller values decrease the contrast ratio.
  • Center: Specifies the percentage of image tonality upon which the expansion and contraction is centered, so the original image values at this percentage remain at that percentage. The default value of 0.5 adjusts the white and black points equally in both directions (the white point goes up, the black point goes down, and whatever values are at 50 percent remain at 50 percent). A value of 0 pins the black point while applying the entire adjustment to the white point, and a value of 1 pins the white point while applying the entire adjustment to the black point.

Sharpen

Applies a Sharpen Convolution filter that selectively enhances contrast in areas of image detail to provide the illusion of sharpness. Should be used sparingly as this operation also increases the sharpness of film grain and video noise. This node has one parameter:

  • Sharpen: Higher values increase image detail contrast. A value of 0 does no sharpening.

Smooth Step

Applies a nonadjustable “s-curve” adjustment to slightly crush the blacks and boost the whites, leaving the black and white points pinned at 0 and 100 percent. Designed to emulate the exposure tendencies of film at the “toe” and “shoulder” of the image. This is a similar contrast adjustment to that made by the Film Look node.

Stretch

Provides separate vertical and horizontal scaling operations that let you “squeeze” and “stretch” the image. You can change the center pixel at which this scaling is performed. This node has four parameters:

  • Horizontal Center: The pixel at which horizontal scaling is centered. The center pixel doesn’t move; instead, the scaling of the image is relative to this position.
  • Vertical Center: The pixel at which vertical scaling is centered. The center pixel doesn’t move; instead, the scaling of the image is relative to this position.
  • Horizontal Scale: Specifies how much to stretch the image, horizontally. Higher values stretch the image outward, while lower values squeeze the image inward. The default value at which the image is unchanged is 1.
  • Vertical Scale: Specifies how much to stretch the image, vertically. Higher values stretch the image outward, while lower values squeeze the image inward. The default value at which the image is unchanged is 1.

Translate

Offsets the image relative to the upper-right corner. This node has two parameters:

  • Horizontal Offset: Moves the image left.
  • Vertical Offset: Moves the image down.

Utility Nodes

The following nodes don’t combine images or create effects on their own. Instead, they output color channel information or extract matte imagery in different ways. All these nodes are meant to be used in combination with other layering and effects nodes to create more complex interactions.

Color

Produces a frame of solid color. This can be used with different layering nodes to add colors to various operations. This node has one control:

  • Color: A standard color control lets you choose the hue, saturation, and lightness of the color that’s generated.

Deinterlace

Removes the interlacing of a shot in one of three ways, corresponding to three buttons. You can use this node to either remove interlacing by blending the fields together, or you can use two Deinterlace nodes to separate the Even and Odd fields of an interlaced shot prior to processing each field separately and reassemble them using the Interlace node. This node has three buttons:

  • Merge: Outputs the blended combination of both fields.
  • Even: Outputs only the Even field, line-doubled to preserve the current resolution.
  • Odd: Outputs only the Odd field, line-doubled to preserve the current resolution.

HSL Key

An HSL keyer that outputs a grayscale matte which you can use to isolate effects using the Alpha Blend node, or simply to combine with other layering nodes in different ways. This keyer works identically to the one found in the Secondaries room. For more information, see Choosing a Region to Correct Using the HSL Qualifiers.

Output

This must be the last node in any node tree. It outputs the effect created within the Color FX room to the main Color image processing pipeline for rendering. If an Output node is not connected to the node tree, that effect will not be rendered by the Render Queue.

RGB Split

Outputs the red, green, and blue color channels individually, depending on which button you click. Each grayscale color channel can then be independently manipulated with different node tree branches, before being reassembled using the RGB Merge node. This node has three checkboxes:

  • Red: Outputs the red channel.
  • Green: Outputs the green channel.
  • Blue: Outputs the blue channel.

Vignette

Creates a simple square or circle vignette. This vignette appears as a color-against-grayscale preview if the Vignette node is viewed directly. When the results are viewed “downstream,” by viewing a different node that’s processing its output, the true grayscale image is seen. This node has the following parameters:

  • Invert: Click this button to make the white area black, and the black area white.
  • X Center: Adjusts the horizontal position of the shape.
  • Y Center: Adjusts the vertical position of the shape.
  • Size: Enlarges or shrinks the shape.
  • Aspect: Adjusts the width-to-height ratio of the shape.
  • Angle: Rotates the current shape.
  • Softness: Blurs the edges of the shape.