Many image-editing programs, including Adobe Photoshop, contain a Sharpen
command that works by increasing the contrast of adjacent pixels. For many
digital images such increases in apparent sharpness come at the expense of
enhanced overall contrast, which not all photographs can handle before losing
highlight detail.
A better bet is to use the unfortunately named Unsharp Mask tool, but novice
users can be confused by the controls. Guessing at settings such as pixel radius
can produce results that may be far from satisfying--or sharp. Nik Sharpener,
from TECHnik USA, makes image sharpening as simple as it ought
to be.
The program plugs into Photoshop 4.0 and later, Corel Photo-Paint 8 and
later, Jasc Paint Shop Pro 5.0 and later, and Ulead Photo-Impact 4.2 and later,
or any other 100-percent Adobe plug-in standard-compatible program.
This plug-in has an interface with six sliders that mimic real-world
considerations. The first two establish the width and height of the image. The
next slider lets you specify the input source, whether it's a small-format slide,
large-format transparency, digital camera, or scanner. There's even a setting for
Advance Photo System film.
You also can specify the kind of output device the image will be printed
with, including inkjet printer, color laser, or commercial offset printing.
Recognizing that not all images are captured equally, an Image Quality slider
lets you establish whether your image is average, very good, or even bad. The
last setting is Printer Quality, which also ranges from very good to bad, so be
sure to be honest about what your printer's capabilities really are.
During the sharpening process, Nik Sharpener avoids aliasing and color
distortion. Its alias-protection process automatically avoids areas where jaggies
might occur and sharpens these areas to a lesser extent than other parts of your
image.
Similarly, the hue protection process corrects color values in areas that
might be distorted during sharpening by conventional digital tools.
In real-world tests, images from Kodak's PhotoCD (as well as 4-inch-by-6-inch
snapshots digitized with an entry-level USB scanner) all showed remarkable
improvement in overall quality. Details in backgrounds went from mushy to crisp,
and edges on foreground showed marked improvement.
When I showed before and after prints made on the HP PhotoSmart 1100 printer,
one experienced photographer told me that the Nik Sharpened print looked
three-dimensional. The only place where the plug-in seemed less effective was
with smaller (330K) JPEG files created by some inexpensive digital cameras.
Nik Sharpener is so easy to use that it could easily be considered a tool
only for beginning digital imagers, but its capabilities can be used by anyone
who works with digital images.
While $120 may seem like a lot to pay for a single plug-in, the first time
you use Nik Sharpener, you'll wonder how you ever did without it. A demo version
can be downloaded from TECHnik.
Sidebar
Behind the Mask
Unsharp masking is a technique used with some image-enhancement programs to
sharpen a photograph. This oddly named function is a digital implementation of a
traditional darkroom and prepress technique in which a blurred film negative is
sandwiched with the original in order to highlight a photograph's edges. In
digital form, it's a more controllable method for sharpening an image.
