How to Find An Image or Image Source on the Internet
A client asked if I could track down the source of an image they found on the web. It was provided to me as an iPad screenshot:
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STEP 1:
The way I did this was to go to google image search:
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STEP 2:
Clicking the camera icon next to the magnifying glass opens up an interface where you can drag and drop or browse to an image file:

STEP 3:
I took a screen shot of the screen shot, cropping out the iPad background, and dragged it onto the image search menu.
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STEP 4:
Here's what Google showed me:
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STEP 5:
Google's best guess was that it was a photo of a "nature reserve" (Google auto input that phrase based purely on the image I used in the search).
Not a bad guess for a bot. But it did not reveal exactly what I was after.
So I redid the search, with my own search terms, "adirondack chairs overlooking lake":
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This is looking better.
I follow the "getty images" link, second from the top. And there it is, halfway down the page:
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This revealed the photographer, and we were able to get in touch to arrange the licensing and use of the image for commercial web purposes.