STRAIGHTENING SCANS IN 10 SECONDS (OR LESS)
If you've scanned an image and it's crooked when you bring it into Photoshop, you can fix it in about 10 seconds flat. Just switch to the Measure tool (it lives behind the Eyedropper tool in the Toolbox) and drag it along the top edge of the image you want to straighten. That's the hard part (and that should give you an idea of how easy this technique is). Next, go under the Image menu, under Rotate Canvas, and choose Arbitrary. Photoshop automatically enters the amount of rotation (courtesy of your earlier measurement), so all you have to do is click OK and bam!the image is perfectly straightened.
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