Carrying film on planes, airport X rays
Its always advisable to place your film, especially exposed film, in your carry-on luggage to avoid the possibility of loss. The best strategy is to carry the film in a see-through plastic bag or a clear refrigerator container and offer it for visual inspection, rather than allowing it to go through airport X rays. Newer X-ray machines are safe for film of moderate speed, but X rays have a cumulative effect; even these films can be damaged if taken through many times. Older machines, especially those made in Eastern Europe or in the former Soviet Union, should be avoided.
The rules
Its easy to find rules about photography: Keep the sun over your shoulder or Shoot only at sunrise and sunset or Shoot only around noon or Never let the horizon run through the exact center of the frame. Its fine to know the rules, but its also essential to break them. Strictly adhering to the rules may ensure mediocre photographs. Top photographers break the rules as often as they keep them. Photography should be spontaneous, alive, and exuberant. If it works visually, do it.