There is a big misconception that "calibration" has anything to do with the validity of a speedig ticket. I'm sure it will vary from one jurisdiction to another, but where I used to work, I would verify the accuracy of the radar immediately after each traffic stop. The "calibration" is done at the factory and then you just test it with tuning forks. I have never seen a radar "out of calibration." On the other hand, when asked "when was the last time your radar was calibrated?" I would say, "it's accuracy was confirmed 10 minutes ago." Make sure that there are calibration/maintenence standards in the jurisdiction before you try to play the calibration card.
As for stationary cameras, it's kind of muddy waters. Technically, a law enforcement officer must witness the violation in order for it to be a chargable offense (non-LEOs will not have enough info about traffic law enforcement and the legal process involved in order to "prove" that a violation occured). Since a traffic camera is not an LEO, the enforceability of the ticket is questionable.
Traffic cameras do not always make a sound judgement call. For example, I once was "caught" turning right-on-red by camera. I did not get a ticket (in WA), but my sister did get one for the same thing (in CA). Some jurisdictions (not sure about AZ) allow for exceeding the speed limit to pass (provided the vehicle being passed was travelling at an unreasonably slow speed).
Also, a "necessity defense" could be argued in the right circumstances. For example, I was once travelling with my cruise control set for the speed limit (75) in the left lane (two lanes in my direction) when I approached along side of a tractor trailer going about 55. Just as the nose of my car was even with the tail of the trailer, I saw his left turn signal come on, and the trailer started to wobble/sway in my direction (it appeard that he did not know I was about to pass him... or he was falling asleep at the wheel or distracted etc). Slowing down would have caused me to end up even with the trailer for a few seconds before falling behind (which according to my perception, would have resulted in a side-to-side impact), so I selected 3rd gear and applied WOT. In the space that I travelled when passing the truck, I reached 95 mph, and then I slowed back down to my preset cruising speed. There was no highway patrol around, but In this case, I'm sure a "necessity defense" would have been applicable.
I'm sure there are more experienced LEOs here than me who can chime in and give their input.
If it were me, I would do whatever I had to do to keep this off my record (traffic school, for example, if it's an option).
