I have never ever seen this contraption, but this was wildly popular in the US at some point in time.
This was the end result:
This was the “certificate issued”:
There were sensible souls:
For those concerned about radiation exposure, the shoe-fitting fluoroscope seemed a dangerous machine. Christina Jordan was the wife of Alfred Jordan, a pioneer in radiographic disease detection, and in 1925, she wrote a letter to The Times of London decrying the dangerous levels of X-ray radiation to which store clerks were being exposed. Jordan noted that while a scientist who dies of radiation sickness is celebrated as “a martyr to science,” a “‘martyr to commerce’ stands on a different footing.”
The author concludes:
The shoe-fitting fluoroscope is a curious technology. It seemed scientific but it wasn’t. Its makers claimed it wasn’t dangerous, but it was. In the end, it proved utterly superfluous—a competent salesperson could fit a shoe just as easily and with less fuss. And yet I understand the allure. I’ve been scanned for insoles to help my overpronated feet. I’ve been videotaped on a treadmill to help me select running shoes. Was that science? Did it help? I can only hope. I’m pretty sure at least that it did no harm.