For this exercise you will start with a scanned photograph and make typical kinds of adjustments. You will learn to use a variety of tools & functions including; Crop, Measure,Rotate,Zoom Tool, Variations ...

Working with the picture. Before doing any adjustments to the picture use the Save As command and save the picture to the desktop with the file name using default settings. The picture has been scanned upside down along with another picture that was on the same page. We are going to select and crop the picture of the girl.

The scanned picture is slightly crooked. Use the Measure Tool to straighten the photograph. Click and hold on the Measure Tool and drag from the lower left corner to the lower right corner. Try to drag along the edge as precisely as possible. (The Measure Tool is located under the Eyedropper Tool. A > in the lower corner of any tool indicates additional tools are available. Click and hold on the tool to see more options. )
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Source: library.med.utah.edu