Yes. These plates have been known for a long time. The only thing in the article that was new was that researchers had decided that the plates were unmanipulated photographs, rather than ones that had been retouched manually after processing. People in the thread here on APUG seem to be taking a different understanding of the article, namely that these are previously undiscovered early photos that push back the date of our art form's invention. They're not that. As I said, its been known forever that photography was invented in the 1820s and as Newhall mentions in his history, its believed that photographs were made as early as the 1790s, but they quickly faded because they were done by a process that caused the image to appear from exposure alone (like POP paper), and no means of fixing them had been discovered. Niépce's photos were the earliest ones that were done with a process that produced permanent light-proof images that have survived to the present day.