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Sharpen

Node icon
Filter

Enhances image detail with Unsharp Mask or edge-preserving Detail Enhance.

Sharpen increases apparent detail by enhancing edge contrast. Unsharp Mask is the classic approach: it creates a blurred copy, subtracts it from the original, and adds the difference back. The Amount controls intensity, Radius sets the blur size, and Threshold prevents sharpening in smooth areas.

Detail Enhance is an alternative that uses edge-preserving filtering. It tends to create a more natural, painterly sharpening effect.

Parameters

Section titled “Parameters”

Pins

ImagePixels
InputRequired
MaskMask
InputOptional
ImagePixels
Output

Filter

ModeChoice
Default: Unsharp Mask
  • Unsharp MaskTraditional sharpening that subtracts a blurred copy to enhance edges. Control amount, radius, and threshold.
  • Detail EnhanceEdge-preserving sharpening that creates a more natural, painterly clarity boost.
AmountNumber
Default: 1.50 Range: 0.00–5.00
Unsharp Mask mode only

Sharpening intensity. 0 = no sharpening, higher = stronger

RadiusNumber · px/%
Default: 1.0 Range: 0.1–25.0 px / 0–100%
Unsharp Mask mode only

Blur radius for the unsharp mask. Small = fine detail. Large = broader edge enhancement

ThresholdInteger
Default: 0 Range: 0–255
Unsharp Mask mode only

Minimum pixel difference to apply sharpening. 0 = sharpen all pixels. Higher = skip low-contrast areas (reduces noise)

Sharpen AlphaToggle
Default: false

Also apply sharpening to the alpha channel.

Usually disabled to preserve smooth transparency edges.

Sigma SNumber
Default: 10 Range: 1–200
Detail Enhance mode only

Spatial extent of the enhancement. Higher considers a larger area for each pixel

Sigma RNumber
Default: 0.15 Range: 0.01–1.00
Detail Enhance mode only

Color sensitivity for edge detection. Lower enhances more aggressively, higher touches only subtle details

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”
  • Use Unsharp Mask with a small radius (0.5–2.0) for general photo sharpening.
  • Increase the threshold to avoid sharpening noise in smooth areas like skies.
  • Detail Enhance works well for giving images a slightly stylized, crispy look.
  • Connect a mask input to sharpen only specific regions, which helps avoid noise amplification in smooth areas.
Section titled “Related Nodes”