218
ADOBE PHOTOSHOP CS2
User Guide
To adjust sharpening in camera raw files
The Sharpness slider adjusts the image sharpening to provide the edge definition you wish. The Sharpness
adjustment is a variation of the Photoshop Unsharp Mask filter, which locates pixels that differ from surrounding
pixels based on the threshold you specify and increases the pixels’ contrast by the amount you specify. When opening
a camera raw image file, the Camera Raw plug-in calculates the threshold to use based on camera model, ISO, and
exposure compensation. You can choose whether sharpening is applied to all images or just to previews.
1
Zoom the preview image to at least 100%.
2
Move the slider to the right to increase sharpening and to the left to decrease it. A value of zero turns off sharp
ening. In general, set the Sharpness slider to a lower value for cleaner images.
If you don’t plan to edit the image extensively in Photoshop, use the Camera Raw’s Sharpness slider. If you do plan to
edit the image extensively in Photoshop, turn off Camera Raw sharpening. Then use the sharpening filters in
Photoshop as the last step after all other editing and resizing is complete.
To specify whether the image or preview is sharpened
1
Do one of the following:
•
In the Camera Raw dialog box, click the triangle next to the Settings menu and choose Preferences from the
Camera Raw menu.
•
(Windows) In Adobe Bridge, choose Edit > Camera Raw Preferences.
•
(Mac OS) In Bridge, choose Bridge > Camera Raw Preferences, or with the Camera Raw dialog box opened in
Photoshop, choose Photoshop > Camera Raw Preferences.
2
In the Camera Raw Preferences dialog box, choose one of the following:
All Images
Applies sharpening to the camera raw image.
Preview Images Only
Applies sharpening only to the preview image and not the actual camera raw image. This
option is for users who do not want to apply sharpening with the Camera Raw plug-in.
Reducing noise in camera raw files
The Detail tab of the Camera Raw dialog box has controls for reducing image
noise
, the extraneous visible artifacts
that degrade image quality. Image noise includes luminance (grayscale) noise, which makes an image look grainy,
and chroma (color) noise, which is usually visible as colored artifacts in the image. Photos taken with high ISO
speeds or less-sophisticated digital cameras can have noticeable noise.
The Luminance Smoothing slider reduces grayscale noise, and the Color Noise Reduction slider reduces chroma
noise. Moving a slider to zero turns off its noise reduction.
When making Luminance Smoothing or Color Noise Reduction adjustments, first zoom in on the preview image for
a better view.