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Brightness/Contrast

Brightness/Contrast
Color

Simple brightness and contrast adjustment with two modes: S-Curve for smooth results or Linear for classic gain.

Brightness/Contrast is the fastest way to make an image brighter, darker, or punchier. Brightness shifts the overall tone up or down, and Contrast controls the separation between lights and darks.

S-Curve mode (default) uses a sigmoid function that gently rolls off highlights and shadows, producing natural results without harsh clipping. Linear mode uses simple gain around the midpoint. It is more aggressive and clips sooner at the extremes.

Parameters

Section titled “Parameters”

Adjust

ModeChoice
Default: S-Curve

S-Curve (smooth sigmoid) / Linear (legacy gain)

  • S-CurveSmooth sigmoid contrast — boosts midtone separation while gently rolling off highlights and shadows.
  • LinearClassic gain around midpoint — more aggressive, clips at extremes.
BrightnessNumber
Default: 0.0 Range: -100–100

Brightness offset; positive brightens, negative darkens

ContrastNumber
Default: 0.0 Range: -100–100

Contrast strength; positive increases, negative decreases

Mask

Mask FitChoice
Default: None

Mask sizing

  • NoneCenter the mask at its native size — no resizing. Unmasked regions are unaffected.
  • StretchStretch the mask to exactly match the image dimensions. May distort the mask shape.
  • FitScale the mask to fit inside the image, preserving aspect ratio. Letterboxes where needed.
  • FillScale the mask to fill the image, preserving aspect ratio. Crops edges if aspect ratios differ.
Notes

S-Curve mode (default) applies a normalized sigmoid for contrast — boosts midtone separation while gently rolling off highlights and shadows. Negative S-Curve contrast lerps toward mid-gray. Linear mode uses simple gain around midpoint — clips more aggressively at extremes. Brightness is applied as an offset before contrast in both modes. Alpha is preserved unchanged. Mask Fit only visible when mask is connected.

Pins: image (required), mask (optional). When mask is connected, the effect is blended with the original using the mask (white = full effect, black = original).

Usage Tips

Section titled “Usage Tips”
  • Use S-Curve mode (default) for most work, as it produces more natural results than Linear.
  • Brightness is applied before contrast, so a small brightness boost followed by a contrast increase can bring out midtone detail.
  • For more precise tonal control, use Levels or Curves instead.
  • Connect a mask input to limit the adjustment to specific regions of the image.
Section titled “Related Nodes”