Efeito céu nublado (bem dark)

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me disseram q no photoshop da pra fazer esse efeito, alguem sabe como???

foto original:

/applications/core/interface/imageproxy/imageproxy.php?img=http://www.alias.com/eng/community/image_gallery/maya_in_print/img/flipbook5.jpg&key=9b8f4d449d35d1250ec814c015649dd3b995c2b2bf800bee8fa1061baa501580" alt="Imagem Postada" />