Originally Posted by CALflyboi

The camera can be used inflight after the portable electronic devices announcement has been made. It may also be used while parked at the gate with the main cabin door open. After the door is closed, you may not used the camera again until the aircraft has reached 10k ft, and the portable electronic device announcement is made. This info is also located in our inflight manual. The FAR's governing this are 91.21 and 121.306.

As for FA's not saying anything, I can't answer for that. The letter you carry does nothing if you are using the camera during one the prohibited periods mentioned. As long as you using when allowed, then there is no problem.