- Lower the Amount value to 300 percent. The
Amount value controls the degree to which the
image gets sharpened. Higher values result in
more edge contrast. The effects of the Amount
value become more pronounced at higher Ra-
dius values as well. So where 400 percent might
look dandy with a Radius of 1.5 pixels, the effect
may appear excessive at a Radius of 3 pixels. An
image exposed to too high an Amount value is
said to be oversharpened, as is presently the case
for our squirrels.
Press Shift+Tab to highlight the Amount value.
Then experiment with the setting by pressing
Shift+� a few times, which lowers the Amount
in 10 percent increments. Figure 7-6 shows a few
examples. The top image is too harsh, the bot-
tom image is too soft, and the middle one is just
right. (Forgive my storybook analogy, but this is
a storybook tale, people.) So do like me and set
the Amount value to 300 percent.
PeaRl Of WISDOm
Users accustomed to Unsharp Mask will notice one value
conspicuously absent: Threshold. Meant to avoid the
sharpening of grain, noise, and other artifacts, Unsharp
Mask’s Threshold option results in an either/or proposition—
an edge gets sharpened or it doesn’t—which may create
pockmarks in an image. I for one am glad it’s missing from
Smart Sharpen.
- Leave the More Accurate check box turned
off. The Smart Sharpen dialog box ends with an
improvement on Threshold called More Accurate.
On first blush, you might assume you should turn
on this option. After all, who doesn’t want a more
accurate sharpening effect? But it’s a little more
complicated than that:- Turn on More Accurate to burrow into the
image and extract all the edges the filter can
find. - Leave More Accurate turned off, as by default,
to trace only the most pronounced edges.
- Turn on More Accurate to burrow into the
Amount: 300%
Lens Blur, Amount: 500% Radius: 3 pixels
Amount: 100%
Figure 7-6.
Sharpening an Image 223