I find the radius should be set to about 1.2-1.8, but if the image has been
resampled from the original this needs to be adjusted. Where an image as
been upsampled the radius needs to be larger (scaled up in proportion to the
enlargement) and where the image has been down-sampled the radius needs to
be reduced (usually to no lower than 0.7-1.0) . Threshold should be set to
avoid sharpening noise and grain. The amount I set so that I can just see no
halo when viewing the image on screen at about 2x print size. This will
usually print fine on an inkjet as error diffusion allow you to use stronger
USM. For other printers such as the Fuji Frontier I view the image at about
3x print size on screen.
On some images I will sharpen a little (30-50%) using a threshold of zero
and then sharpen some more as above with a higher threshold in an attempt to
sharpen the whole picture a litttle (without significantly affecting
grain/noise) and to "fully" sharpen the main edges.
Steve
----- Original Message -----
From: "Todd Flashner" <tflash@earthlink.net>
To: <filmscanners@halftone.co.uk>
Sent: Monday, September 10, 2001 1:03 AM
Subject: Re: filmscanners: NikSharpener Pro
> Isn't this "boundary" the halo that USM is built upon? The idea of USM
(and
> this is way to short an explanation) is to introduce just such edge
contrast
> around and/or between objects and transition zones. The width of these
halos
> are controlled by the Radius slider in the USM dialog box. Try decreasing
> your Radius substantially to see if that helps.
>
> Also check out these two articles:
>
>
>
>
>
> Todd
>
>
> > Brian,
> >
> > Honestly, it is too soon for me to answer than question. The scanning
I've
> > done with it so far has been low-res web scanning. I certainly haven't
> > noticed the boundary problems you described. I have not, however,
scanned
> > for printing at full resolution. Once I do that, I'll let post more
> > results. For the purpose I've used it so far, I've been very pleased.
> >
> > Tom
> >
> >> Tom,
> >> I find your comments intriguing. Could I ask a few questions? I find
> >> that when I sharpen using Photoshop tools, there is oftentimes an
> > artificial
> >> dark or light line (sharpening artifact) that appears at the
juxtaposition
> >> or boundary of a dark and light area. This causes me to spend a good
deal
> > of
> >> time cleaning these things up. Does this this sharpening plugin
eliminate
> >> this problem? If it does I would say the price was worth it. I would be
> > most
> >> interested in your observations on this.
> >>
> >> thanks,
> >>
> >> Brian
> >>
> >
>
>
