On Sun, Jan 03, 2021 at 02:32:30PM +0100, Karsten Hilbert wrote: > The margin of error will be larger than the precision of approximation :-)
For most of the image parameters, a Dr can decide whether the x ray looks right in absolute terms. Comparing gives just a rough basis for a technician. Same holds good for the distance part of it. Next time I get a chance I'll have a coin x rayed with no parallax. BTW I'm told they do not rely solely on distance shown on the X ray image. It's their 'first approximation' anyway. Even assuming a well calibrated instrument there are factors related to placement that require the margin for error. Nevertheless, I dislike calibrating these without a spec or a documented basis. But that's all we can do.
