Just arrived back in Japan after 7 weeks in Canada (and Greenland). 13 flight segments in multiple airports, was able to get hand checks at every one without needing to explain anything, although in larger airports (YVR, YYZ) the screening process took a long time since most people did not pack their liquids properly which meant that security personnel had to examine every item. When it came to checking my film (and occasionally cameras) the process was fairly quick. The only airport I had a problem in was Yellowknife, where they made me open every roll of 120 because they needed to see the actual film rolls. When I complained about it they gave me a card to direct my complaint to, so that was unexpected. Also, somewhere along the way (maybe at that same airport) a bag a film (unexposed) went missing, so I lost 14 rolls which luckily I was able to replace while in Ottawa. Airports I flew through on this trip were:
Narita (NRT), Japan
Mexico City (MEX), Mexico
Dawson (YDA) - no x-ray machines whatsoever here, just a guy who prints the tags and loads your bags directly onto the plane
Kangerlussuaq (SJF), Greenland - flew there are and back on charter planes. Upon leaving Ottawa we drove straight onto the tarmac and got onto the planes, bypassing security entirely; on the way back from Greenland, was able to get a hand check at the airport.