[jjeaff]

That's interesting. But, assuming the research found it possible to verify which device a photo came from based on the sensor noise, doesn't that kind of go against the idea that there is a lot of entropy in sensor pattern noise?

[OJFord]

No, because you could have it that the device is always identifiable, but nevertheless producing a randomly varying sequence of images.

Take printers for example, with some known to print a signature. Clearly they can still print a sheet a solid colour (or a number 0-100, or something character or whatever) at random (given some random source & control for doing so I mean) despite the device being identifiable.