I attach a couple of photographs I took in the summer, one of a dental X-Ray plate exposed to a LION tube 'post event' (grey) and another micro photograph of the inside of a fuel-tube fragment.
There are some really small and sharp dots on the X-Ray plate.
Most tubes have cylindrical shape whereas a plate usually is flat and not very flexible.
That would make it difficult to achieve good resolution.
Was the plate flexible or was the tube flattened?
Did you make a duplicate to verify same pattern?
Do you have any idea what caused the dots?