One piece of advise I would offer to anyone travelling with photography equipment is this:
Print out the baggage policy from the airlines website. If you have a hard copy of their policy with you it can save a lot of problems.
Some problems with gate/baggage personnel comes from the fact that they either don't know their own companies rules, or that they are changing the rules for their own reasons.
I started doing this after a trip to Dominica. We were on a group photography trip several years ago. The AA counter personnel in Dominica had no clue about the companies baggage rules. When we tried to leave the country they were not going to let us take all of our bags with us. When they could not give us an answer on what would happen to our bags that did not get on the flight things got a bit heated.
We asked if we could pay an excess baggage fee, we asked if the baggage would be put on a later flight, we asked if our bags would be sold at the local flea market after we left, we even asked if their family was going to be using it after we were gone. All questions were answered with a shrug of the shoulders.
Luckily, someone in the group had the rules printed out from the AA website. They even agreed to take our baggage allowance as a lump sum amount for the whole group. (There were a couple of non-photographers in the group with a lot less luggage.)
They took us as couples (or as singles) into a security room. In the room was an airline counter person, a baggage scale, and a security officer with an automatic weapon. First they weighed our checked bags, and wrote the information down. Even though they were taking the group as a whole there were still limits on the individual bag weights.
My wife and I were called into the room. They first weighed my wife’s checked bag, wrote down the number, and put it aside. Next they weighed her carry on bag, wrote down the number, and gave it back to her.
It was then my turn. They weighed my checked bag, and it was over the limit. I took batteries, chargers, and odds and ends out of it until it was just at the limit. I put these items in my carry on bag. Once they had written don the weight it was time for my carry on. It was now over the limit. Right in front of the airline employee, and the armed security guard, I took things out of my carry on, and put them back in my checked bag, until the carry on was within limits. I was waiting for them to realize what I was doing and stop me, but they never did.
All of our luggage made it onto the plane, and I did not get shot.