In capture, turn off all sharpening, assuming a NEF file. Minimize
any effort to recover detail from shadows or to increase "exposure"
by more than 1 stop. (Next time, remember that a good histogram
that goes virtually all the way to the right, will capture the
least amount of noise.) If the file is an original JPEG, go on to
the next step in Photoshop.
In Photoshop, duplicate the image. Isolate on the duplicate each
individual channel by turning off the eye symbol in the other
channels. Find the noisiest channel, which is usually the blue
channel, by inspecting the image at 100% or even 150%. Look for
color speckles and black chunks. Both are potentially
objectionable noise, unless, of course, the image was of a colorful
speckled object with chunky black spots.
Now is the time to try an adjustment layer or two to recover any
shadow detail that you simply must have. Try to avoid enhancing
the noise. Stay away from Hue/Saturation, a notorious noise
producer.
Now, let's tackle the noise directly. With the noisiest channel
the only active channel, use Filter> Blur> Gaussian Blur to slightly
blur that channel. Try 1 or 2 pixels, but experiment by toggling
the preview on and off. When the noise chunks begin to become
fairly indistinct, that's probably enough blurring. Don't blur it
so much that the noise is "vaporized," That will probably cost you
too much in detail. The blue channel may be heavy with important
picture details that you want to soften, but not obliterate.
Now do a targeted sharpening that avoids sharpening the noisy
areas. There are lots of ways to do this. For example, if there
is a prominent face in the picture, and you want it to be sharp, do
a selective sharpening via USM on a layer or withing a selection of
eyes, brows, mouth, and some hair in the plane of the face. Don't
sharpen the rest of the face or the rest of the picture, if
possble. Try to paint with sharpening on only the important
features. If there are other areas in the picture that must also
be sharp, extend the sharpening to them, but avoid sharpening
blurry areas and dark, noisy areas.
If the image is fairly sharp to begin with, you may be able to get
away with sharpening only the red channel using USM with only the
red channel showing (assuming that the red channel had the least
amount of detail compared to the other channels. Usually the
remaining detail in the red channel consists of edges that you will
want to sharpen.
Once sharpened, the red channel should contribute some sharp edges
to the final image, including eyes, and other facial features, or
other similar types of edges on other types of subjects. Right
after applying the USM, you can also try to use Edit> Fade Unsharp
Mask, and set the blend mode to "luminosity." This blend mode will
minimize the effect of the sharpening on the color noise. If you
decide to sharpen the green channel, too, try to use the same
settings as for the red channel to avoid strange interactions
between the two sharpened channels.
You just might find that these techniques lead to less loss of
detail than Neat Image or the other noise reducers. You should
also be aware that Yves P. has had good results applying Neat Image
in a layer of an image, and then adjusting the opacity of the layer
to find the best mix of noise reduction and detail retention. I'm
just not patient enough for this, and I can get pretty good results
just using Photoshop. That technique also frequently crashes my
ram-hungry computer. But remember, the final output is strictly a
matter of what pleases your eye, not mine.
I used all of the above techniques in my recent image of naturalist
Dr. Jane Goodall at a recent appearance in the S.F. Bay Area. This
picture was taken in a very dark auditorium, and I was forced to
use ISO 1600 and a slow shutter speed of 1/50 sec. to capture a
full stop underexposed image. (I should have used ISO 3200!!!)
Despite all the difficulties, the image luckily turned out very
sharp, yet ethereal, almost as if I knew what I was doing. Notice
that there is no "plasticky" look to the image, which is a
tell-tale sign of use of a noise reduction algorithm.
I have a raw file I shot at ISO 800 (sunny day) - they need a 8x10
and it's soooo noisy!!! What's the best process in Capture? Just
levels or do you have other combos that have worked for you???? Is
there a Capture/PS7 fix that might work better? I HAVE to make
this reprint better!!!!
Thanks!! Missy
--
Bill Adams
http://www.pbase.com/bill_adams
. Thanks to you for your kind words as well. I just try to pass along what others pass to me, that Karma thing you know.