1. Change some default settings:
Eyedropper tool: Select the tool, then change to 3 by 3 Average in the options bar
Curves settings:
• Double click on the black eyedropper and change RGB settings each to 10
• Double click on the white eyedropper and change RGB settings each to 244
• Double click on the gray eyedropper and change RGB settings each to 133
2. Open the image that needs adjusted. Make sure it’s in RGB mode.
3. Mark the best black:
• Add a threshold adjustment layer. (Click on the adjustment layer icon at the bottom of the layers palette and choose threshold.)
• Slide the slider all the way to the left. Then slide back to the right just until a large enough black area appears. Click OK.
• Select the Color Sampler tool from the Eyedropper tool flyout options.
• Click on the background layer in the layers palette, and click in your black area. (TIP: turn on caps lock to get a cursor that’s easier to work with.)
• Delete the threshold layer.

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