That tic-tac-toe overlay grid you see when you activate the Crop tool in the Develop module is based on the Rule of Thirds. If you press the O key you can cycle through other overlays to assist you with image composition. Give it a try!
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About the Author: Gene McCullagh
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Gene is an Adobe Community Professional and and Adobe Certified Expert in Photoshop Lightroom, Photoshop, and InDesign, and an avid Lightroom fan. He belongs to the Professional Photographers of America (PPA) and the National Association of Photoshop Professionals (NAPP). Gene also the Co-Founder, Manager and a frequent blogger for the Dallas Fort Worth Adobe User Group (DFWAUG).
In addition to running Lightroom Secrets, Gene also contributes to O'Reilly's media blog, moderates on the Adobe forums, and helps out on lightroomforums.net.
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