Advanced Scanning
(The mouse pointer displays as a black triangle when the Alt or Option key is pressed.) The software makes your selection black and adjusts all lighter tones accordingly.
Adjusting Image Appearance Using Tone
Curves
When an image needs adjustment, it is usually because the image is too dark or too light. However, it’s not unusual that only parts of an image need adjustment. In such cases, you can use a tone curve to adjust only those tones in an image that are too dark or too light.
A tone curve displays the richness of the various tones in an image, from light tones to darker tones. These tones refer to shades of gray between black and white, or the saturation (intensity) of a color. You can adjust the gray (or color) tones in the middle range (midtones) as well as the highlights and shadows, by changing the shape of the curve.
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