So what are the sliders doing? With SilverFast USM
takes place on-the-fly in Lab mode hence the % values and references to
grey in the user manual.
Intensity will determine the amount of
sharpening that takes place. Typically we should set low values between 15 and
40%. Occasionally values above 50% can be used, but these are rare.
Threshold determines where the sharpening will
take place ( i.e. contrast between two adjacent pixels). Values
between 2 and 6 are normal. If high Intensity values are used
it will be necessary to further increase the Threshold.
"Sharpen down to" is a bit more
complex to explain but basically determines how far into the shadows
the image will be sharpened. Go too far down and shadow noise will
become more pronounced than we would normally desire. It's probably
better to experiment with different values.
I tend to leave "Light and Dark Contour"
at the default values. Modifying either will tend to cause black or white specks to become less or more pronounced. Increase
"Light contour" value and
white specs will jump off the screen at you, likewise increasing the
"Dark contour" value will cause any dark specs to become even blacker.
Experimentation is the name of the game with these two sliders. If the
image has lots of speckles it is certainly worth adjusting one or both
Engage the "Highlights soft" option
means that the sharpening effects will not be applied to highlights.
Each of the above adjustment sliders works in "real-time"
so you can easily see the effect of a change in the high-resolution scan
window. This window can be scaled up to 8x magnification, but I rarely find
is useful above 2x magnification. Hopefully, through some experimentation
you to will get less grainy scans than appears to be the case at present.