Apple Aperture 2 - Manual (Page 352)

352 Part III Performing Image Adjustments
Using the Boost Controls
The Mac OS characterizes each digital camera’s RAW file format to determine an optimal
contrast setting. The Boost controls allow you to set the strength of the contrast when the
RAW file is decoded. The Hue Boost controls are used to maintain the hues in the image
as the contrast is increased using the Boost controls. When the Hue Boost parameter is
set to 1.00 and the Boost parameter is set to 1.00, the hues of the primary and
secondary colors are pinned to their pure color values, resulting in a shift of all the hues
in the image. For images that consist of saturated primary and secondary colors, such
as an image of flowers in a lush garden, shifting the hues to their true values has a
desirable visual effect. However, this is not visually desirable for images containing skin
tones. Shifting the hues most often causes the skin to appear yellow. Setting the Hue
Boost parameter to 0.00 increases the color contrast in the image while preserving the
original hues in the image.
To adjust the Boost parameters:
1 Select a RAW image imported with or migrated to Aperture 2.0 or later.
The version is indicated by the RAW Decode Version pop-up menu.
2 In the Adjustments inspector or the Adjustments pane of the Inspector HUD, adjust the
Boost parameter by doing one of the following:
 By default, the Boost slider is set to 1.00. Drag the Boost slider to the left to decrease
the amount of contrast applied to the image during the RAW decoding process, and
drag the Boost slider back to the right to increase it.
 Click the left or right arrow in the Boost value slider to adjust the contrast by 5 percent
increments, or drag in the value field.
 Double-click the number in the Boost value slider, then enter a value from 0.00 to 1.00
and press Return.
A value of 0.00 applies no contrast adjustment to the image during the RAW
decoding process. A value greater than 0.00 increases the contrast adjustment to the
image. A value of 1.00 applies the full Apple-recommended contrast adjustment for
the specific camera model.
Use the Boost slider and value slider to
adjust the amount of contrast applied
during the RAW decoding process.