Photographic records and uncertainty about completed wiring

Run-on keeps timestamped photographs of his work, particularly where the finished installation will be difficult to reach. He describes being told that polarity had been reversed on components in a 24-volt system, although he could not reconcile that report with his photographs. He acknowledges that he could be misinterpreting the images or could have made a later mistake, alongside the possibility that somebody else changed the work. His admission of previous mistakes gives the photographs a role in checking his own work as well as recording its completed condition.