GIMP/Levels
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< GIMP
The levels tool is an easy and powerful tool for adjusting the tones of an image. It allows more precise control of contrast than the Brightness-Contrast tool, but doesn't give the user the complete control of Curves.
[edit] Input Levels
Input levels control the contrast of the picture. The end points control the black points, and the white points.
This tool can be used to simulate setting a white point. For images such as Image:PSF B-70002.png, setting a white point is critical in extracting useful images such as Image:Backstroke (PSF).png.
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