Not saying I knew or sensed any of that — it was immediately clear which window. The camera stood in front of it, pointing at it. A window to the left of a fireplace, as you faced the southern wall. I walked up to the glass and looked out, saying something along the lines of, So, this is the actual view… I have a gift for profundity at important moments.

“Well, not exactly,” said Mahé.

He explained that in the course of studying every inch of the room, which he and his colleagues have spent years doing, they’d found that the window was in a slightly different place on the wall than it had been in 1827. “This fireplace,” he said, “was not original to the house.” When it was added, the window was moved to accommodate it. “About 70 centimeters to the left,” Mahé said.

One of the other prominent neo — Niépcians, Jean-Louis Marignier, had used computer modeling to overlay and compare the current view from the window with the one in the View from the Window. Proceeding geometrically (“like a surveyor,” Mahé said), Marignier had detected this almost imperceptible shifting of position. A few of the objects in the picture were still out there to be used as fixed points.

“In fact,” Mahé said, “we just found a new one!” His excitement about it was still fresh and so less guarded. “Yes, this is something interesting,” he said. “You know, I have held the actual plate of the View from the Window in my hands two or three times. But the last time I saw it” — at the Harry Ransom Center in Austin, Texas, where it is housed — “I noticed a little white smudge in the corner, and I realized it shows a building that still exists on this landscape.” He put his face almost against the glass and pointed out, over the fields and houses of Saint-Loup-de-Varennes. I followed his gaze. In the distance one could make out a wall. It was partly obscured by a tree, barely visible. But the team had checked it out, and it was old enough to have been there. Its position on the plate corresponded to where it was standing, once the 70-centimeter adjustment had been allowed for.

I asked Mahé about his experience handling the plate at the Ransom Center, which triggered in Mahé a story not from his personal history but from the past of the picture itself, which he knew almost as well as his own. The plate, he told me, had almost been lost, “passing through many hands,” as the auction catalogs say, before disappearing for a good 50 years starting around the beginning of the 20th century. The art of photography flourished and became dominant, but the image that had started it all was missing. In 1952, one Mrs. Pritchard — the daughter-in-law of one of the many men who’d once owned the plate, and recently widowed — was taking inventory of her late husband’s estate and noticed mention of an unmarked trunk, which according to the records had been lying there for more than 30 years, in a kind of storage locker down by the Thames. Inside it, she found old clothes, family relics, and the Niépce plate.

Shapton’s illustration of Niépce’s bust.

Part of the violence done by Daguerre, in his vainglory, calling his pictures daguerreotypes, was that Niépce’s contributions to photography were neglected and even snobbishly dismissed in the decades immediately following his death, Mahé told me. Much was lost that way.

His story moved me 70 centimeters to the left. Or not the story so much as the alternative reality it implied, one in which the plate was never relocated, was thrown into the Thames, and so for modern historical purposes never existed. The View was Niépce’s pinky on the stirrup of the galloping horse of history. Had it vanished, he would be, I suppose, a legend or a phantom in the footnotes of early photography — the Frenchman with the strange name, who was supposed to have preceded Daguerre and taught him, but got rubbed out of the narrative. And of this mysterious person’s pictures, none survive except some sun prints, basically photocopies. Yes, we would speak of Niépce with the fascination that attends great obscurity, but with a spoonful of sophisticated doubt, too, saying things such as, “Perhaps his pictures were not quite so astonishing as observers would have us believe, especially considering that Daguerre’s advances were still years off when Niépce died.”

I would not be standing in this room. Would never have been haunted by these rooftops. Would not really understand that it started here. Would not have the true sense of what photography’s dream-like primordial origins looked like.

It wouldn’t matter. Because we wouldn’t know we didn’t know it, but what a disaster. We would have the story so wrong.

At that moment I saw maybe the last thing I would have predicted, had you told me that I would look out that window one day: a backyard trampoline. The family who owned the property lived in one of the other buildings, but I had forgotten about them, so complete was the time-travel effect. I pictured the floppy-haired heads and faces of provincial French schoolchildren sailing into the air, into my line of sight, down again, then bouncing back up. It was jarring, but also, somehow, a perfect addition to the View. There was life in it, and a spirit of play that Niépce had known and held onto longer than some. What had Niépce given us, after all, in what he invented here, if not a way to maintain our grip a bit longer on the spectacle of the world?

I retrieved my phone from my pocket and took a picture.