How do I Identify a Printer's ID Signature?
- 1). Print out a document. The page does not have to be filled as the markings will appear no matter how little is printed.
- 2). Switch off the lights and shine a blue LED light on the piece of paper. Inexpensive versions are available for purchase online. Run the light over the paper and you'll see a series of small dots. The dots appear black under the blue light.
- 3). Place the page under a microscope if you do not have a blue light, at a magnification of at least 10x or more and you will see the dots.
- 4). Send your sample print out to the EFF if you are curious to find out more about what the dots mean. The EFF is currently conducting research to categorize the markings of each printer so it is no longer such a mystery to the public (see Resources).
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