One of the most daunting challenges facing underwater photographers is deciding what equipment from your expanding inventory of dive and photo gear to bring with you on your next dive trip. Now that most major airlines are charging fees for checked and overweight bags, this decision has become even more complicated. So this month I'm going to offer some insight into how I travel—the most essential gear to bring and a few other nuggets about successfully navigating the Transportation Security Administration  (TSA), customs, and a nightmarish gauntlet of regulations, policies, and fees.
The most important thing to remember is that the rules of air travel, both domestic and international, are always changing and aren't enforced universally. What flies in San Francisco may not get you through security in Los Angeles. The fact that you were able to carry it onboard in Newark doesn't mean you'll be able to in Cancun. These inconsistencies of policy enforcement require a certain degree of flexibility and calmness on your part. No matter how much time and effort you expend in packing the perfect bag, stuff happens. While you may not get the exact resolution you want through friendly negotiation, you won't get anything by being angry and unpleasant. A few tips:
My ultimate goal when embarking on an international dive trip is to capture the best images I can—and then bring them, myself, and my gear home safely. Therefore, I do all I can to ensure that my gear is in perfect working order before I leave. At least three weeks before the trip, I make a dive in my local dive shop's pool to test my housed camera gear and strobes, regulator, BCD, and dive computers. If anything needs servicing, I still have time to ship it to the proper technician and have it returned to me in time for the trip.
Once I know that my gear is ready for travel, the packing mania begins! I generally travel with four pieces of baggage: two carry-ons and two checked bags. Here is a breakdown of their contents, along with some helpful tips:
This contains all of my travel documents, my wallet, plane tickets, itinerary, passport, any medications that I need for the flights and the first few days abroad, ear plugs, eye shades, a small bottle of hand sanitizer, my cell phone, iPod and chargers, portable external hard drive, and reading material (Amazon's Kindle  is a wonderful alternative to carrying heavy books). 
A new addition to my backpack for most trips is a Spot Satellite Messenger . The Spot is a neat little gizmo that sends your preprogrammed personalized email messages to your friends and loved ones telling them that you're fine and giving them your location by latitude/longitude coordinates. This has drastically reduced my worries about making very expensive satellite phone calls home. It is fun to track your progress using these messages, and in the event that you are not fine, the Spot can send out a distress signal that informs local authorities of your location. Thankfully, I have never had to use this particular feature.
This is where all of my camera gear goes. I would highly recommend against ever putting cameras, lenses, or other delicate electronic gear in your checked baggage. For most trips, this backpack  contains: two camera bodies, laptop computer and electric adaptor, six lenses, filters and diopters, lens cleaning products, memory cards and two card readers, camera batteries and charger, camera manuals, dust blower, and so on.
This practically indestructible beast  holds my more sturdy and non-electronic photo gear, including: housing, lens ports, strobes and spares, strobe synch chords, strobe arms, connectors and other hardware, dive light and charger, housing accessories (spare o-rings, silicon grease, small tool kit, etc.), and at least twenty-four Sanyo Eneloop AA NiMH rechargeable batteries , along with a Maha 8 slot battery recharger and a small travel power strip. These batteries power my two strobes, as well as backup dive lights. 
A note about batteries: it is time to stop using disposable alkaline batteries! The technology for rechargeables has gotten so good that they typically outperform alkalines with shorter recharge time and longer lives. Our landfills are already loaded with enough toxic crud to last centuries without continuing to heap tons of spent batteries on the pile.
With all of the above equipment in the hard case, this checked bag ends up weighing right around 50 pounds, which is the weight limit of most domestic flights in economy class.
Into this final piece goes all of my dive gear (wetsuits, fins, mask, snorkel, BCD, regulator, two dive computers, etc.) as well as my clothes and personal items, including toiletries, medications, and an empty 1 liter Nalgene  water bottle that I use throughout the trip instead of wasting dozens of plastic bottles. The aforementioned collapsible duffle  goes in here as well.
After nearly fifteen years of pretty far-flung dive photo travel, I still realize within a day or two of arriving at my destination that I have brought too many clothes. Almost every live-aboard dive boat or resort will be happy to launder a few items for you for a small fee. So go light on the clothes, especially if you are pushing the weight limit for check-in baggage. I'd rather wear a dirty shirt for a few more days than miss a killer shot because I made room for clothes instead of the right gear. Now...go plan a trip and pack like a pro!
Have fun and dive safe,
To view more of Jeff's work, log on to: www.jeffyonover.com 
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Note: The products discussed here represent the opinions of the columnist and should not be considered endorsements by the Coral Reef Alliance.