Huuh! I was always asking myself how the "real" spotter can only take note of the regos, and not shooting photos of the aircraft. You are already at the airport and just have to press a button on your camera to have that special plane on film for years to come. Why only take registrations??
Becaus everytime I am at the airport I see at least 50 aircraft. At least three shots of each is what you need to have it for all times. As I used to be there at least every other week, that sums up to about 4000 photos a year, or about 180 rolls of film. Aside from the fact that you`d have a hard time storing those prints, you`d end up paying somewhat in the $2000 range for films and developing. That`s why I only took pictures of very special aircraft and only noted the regs of the 99% of "normal" traffic.