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The Showfoto Handbook
are sharp, and there is still too much area noise, then Texture detail could be used to reduce
noise without blurring edges. Another way would be to decrease Radius and to increase Edge.
• Sharpness: this control set the sharpness level. This value defines the pixel distance in which
the filter looks ahead for luminance variations. When this value is increased, then spikenoise
is erased. You can eventually readjust filter Edge, when you changed this setting. When this
value isto high, then the adaptive filter cannot longer accurately track image details, and noise
can reappear or blur can occur.
• Edge: this control set the edge accuracy for sharpness. This value improves the frequency
response for the filter. When it is too strong then not all noise can be removed, or spike noise
may appear. Set it near to maximum, if you want to remove weak noise or JPEG-artifacts,
without loosing detail.
• Erosion: this control set the phase shift for edges. This value can be used to erodes singular
spikes and it has a smooth effect to edges, and sharpens edges by erosion, so noise at edges
is eroded. The effect is dependant from Sharpness, Damping, and Edges. Set it to minimum,
if you want to remove weak noise or JPEG-artifacts. When this value is increased, then also
increasing Damping is often useful. This setting can provides sharpening and antialiasing
effect to edges when spike noise is corrected.
• Luminance: this control set the luminance tolerance of image. It’s recommended to use only
Color or Luminance tolerance settings to make an image correction, not the both at the same
time. This settings don’t influence the main smoothing process controlled by Details settings.
• Color: this control set the color tolerance of image. It’s recommended to use only Color or
Luminance tolerance settings to make an image correction, not the both at the same time. This
settings don’t influence the main smoothing process controlled by Details settings.
• Gamma: this control set the gamma tolerance of image. This value can be used to increase the
tolerance values for darker areas (which commonly are more noisy). This results in more blur
for shadow areas.
• Damping: this control set the phase jitter damping adjustment. This value defineshow fast the
adaptive filter-radiusreactsto luminance variations. If increased, then edgesappear smoother,
if too high, then blur may occur. If at minimum then noise and phase jitter at edges can occur.
It can suppress spike noise when increased and this is the preferred method to remove it.
• Save As and Load: these buttons are used to do just that. Any Noise Reduction parameters
that you have set can be saved to the filesystem and loaded later.
• Defaults: this button resets all settings to default values.
3.1.4.4.2 Noisereduction in action
This is an example of how the noise reduction can change your life. The original image is (1) and
the corrected image is (2). The noise reduction was applied using default settings.
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