Practical Artistry: Light & Exposure for Digital Photographers

162 Digital Darkroom

Noise Reduction

Noise Reduction

If you shoot a photo with the shutter open for a long

amount of time, or at a high ISO, or in certain light-

in

g conditions, your capture will include a great deal of

noise despite the diligent effort of your camera’s pro-

ces

sor to reduce it (see Chapter 4 for more information

about noise and its causes).

In Chapter 4, I gave some examples of using noise cre-

a

tively in your photos. But a lot of the time, I don’t want

to use noise creatively, I just want the noise to “be gone.”

There are tools that can help you vanquish noise as

part of the conversion process in Adobe Camera Raw.

You’ll also find noise reduction filters in Photoshop. In

addition, third-party vendors provide powerful noise

reduction software as Photoshop plug-ins or stand

-

a

lone products (see sidebar on page 113).

It’s often worth trying to reduce noise in the luminance

data of a photo without reducing noise in the color data

quite as much. Luminance r

efers to the black and white

information in a color photo; luminance noise tends to

be more visually objectionable than noise in the color

data of a photo.

It’s a fact of the digital photography universe that any

effective noise reduction technique also softens the

photo.

I took this almost ten-minute exposure from the top of Half Dome

looking down at Yosemite Valley, with the setting moon and the

night ...