There is a new class of X-ray machine with higher intensity radiation. It reputedly
can fog film, even slow film.
Putting it in a Lead bag or case reputedly wont make any difference, as the newer machines are programmed to keep bombarding inpenatrable objects until they can penetrate.
Objects in luggage they still can't penetrate are supposed to be followed up. I don't know if this simply neans a hand-check--or opening and runing it though again.
You can ask for hand-checking-but airports get busy and may have other concerns.
Just a 'heads up'.
And I don't know how common the newer x-ray machines are.
Buying and developing conventional film abroad or at resorts can be a rip-off. And daDOOG don't know the answer.
But I'm willing to learn

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D

G