The first test made an empty doorway look like a new source.
Sera stopped, checked the display and looked through the opening again. Nothing had entered. Juno stood on the far side holding the known test signal at a steady output.
“You moved,” Juno said.
“So did the reading.”
“Too much.”
She wrote down the failure before adjusting anything. If they remembered only the successful attempts, Sera would carry a tool into the next round that had never been tested against her own movement.
Their permitted practice space contained a short corridor, a turn and two marked positions for the test source. Kellan had set ordinary floor markers so Sera could repeat the same approach. Tessa watched from the corner, measuring how often Sera’s attention dropped from the route to the display.
Juno adjusted the reference interval. On the next pass, Sera’s movement produced a smaller change, while Kellan bringing a second known source around the corner produced a clearer spike.
