Apple Aperture 3.5 - Manual (Page 273)

Chapter 7 Make image adjustments 273
Adjust contrast, clarity, and saturation
You use the Enhance adjustment controls to set the contrast, definition, saturation, and vibrancy.
If you want to adjust the difference between the dark and bright areas of the image, you can
modify the Contrast parameter.
Before Contrast adjustment After Contrast adjustment
When you want to add a little clarity and definition to an image without adding too much
contrast, you use the Definition parameter controls.
Before Definition adjustment After Definition adjustment
You can change the value for the Saturation parameter to either give your image an extra burst
of color or tone down the color palette by desaturating the image.
Before Saturation adjustment After Saturation adjustment
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