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Exposure

Exposure
Color

Adjusts exposure in EV stops, working in linear light for natural-looking brightness changes.

The Exposure node applied to a source image: original (left) and result (right).
Side-by-side comparison: the original image on the left and the same image after the Exposure node on the right.

Exposure adjusts image brightness in photographic stops (EV). +1 EV doubles the brightness, -1 EV halves it. Because it works in linear light space (degamma → adjust → regamma), the result looks much more natural than a simple brightness offset, especially when darkening.

Offset lifts or lowers the black point in linear space, which is useful for filling in crushed shadows. Gamma provides a final midtone correction after the exposure and offset are applied. In an 8-bit document, Offset reads and edits as a whole code value from -255 to 255 to match the rest of the editor’s 8-bit controls; a 32-bit (float) document keeps the -1 to 1 fraction with its full overbright headroom.

Parameters

Section titled “Parameters”

Pins

ImagePixels
InputRequired
MaskMask
InputOptional
ImagePixels
Output

Adjust

Exposure (EV)Number
Default: 0.00 Range: -5.00–5.00

Exposure in EV stops. Works in linear light for natural results. +1 EV doubles brightness, -1 EV halves it

OffsetNumber
Default: 0.000 Range: -1.000–1.000

Black level shift in linear space. Positive lifts shadows, negative crushes them

GammaNumber
Default: 1.00 Range: 0.10–5.00

Gamma correction. <1 brightens midtones, >1 darkens them

Mask

Mask FromChoice
Default: Luminance
Color image connected to the mask input

How the connected color image is read as a mask

  • LuminanceRead the image's brightness as the mask. The default.
  • AlphaRead the image's transparency as the mask.
  • RedUse the red channel as the mask.
  • GreenUse the green channel as the mask.
  • BlueUse the blue channel as the mask.
Mask FitChoice
Default: None (native size)
Mask connected

How the mask is sized when it doesn't match the image

  • None (native size)Center the mask at its native size, with no resizing. Unmasked regions are unaffected.
  • StretchStretch the mask to exactly match the image dimensions. May distort the mask shape.
  • Fit (letterbox)Scale the mask to fit inside the image, preserving aspect ratio. Letterboxes where needed.
  • Fill (crop)Scale the mask to fill the image, preserving aspect ratio. Crops edges if aspect ratios differ.

Usage Tips

Section titled “Usage Tips”
  • +1 EV doubles brightness, -1 EV halves it. Think of it like camera exposure compensation.
  • Use Offset to lift shadows; highlights clip naturally, so the visible effect is strongest in dark areas.
  • Gamma > 1 brightens midtones, Gamma < 1 darkens them. This is similar to Levels gamma but applied after exposure.
  • Connect a mask input to apply the exposure adjustment to only part of the image, enabling selective dodge and burn.
Section titled “Related Nodes”