Just go to the image search, click on Advanced..., and tick the photo content box. Enter your search term as usual, say, Mickey Mouse, and the search results will now contain a lot more photos than e.g. cartoon drawings in comparison to a normal search.

Ionut Alex. Chitu, who wrote about the new option at his blog, says a simple way to find photos would be to restrict the results to JPEG files, but a search for Gmail shows that many people use the JPEG format for logos and screenshots.

Other image categories Google already offered were news content and faces.

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