35 is perfect for 95% of shooting, I'd say. I made due with even wider on a two week trip. Forget the Bronica. Absolutely a bad idea to bring a brick-like beast of a camera on a long trip. Take it from someone who once tried it.
Humidity - you will have a hard time getting airports and other travel ports to allow you to keep your film wrapped if you are shooting medium format. Shooting 35mm is best, because you can replace everything into the canisters.
BUT : you can usually stuff 120/220 film in your coat pockets and make it through scanning stations without trouble. 35mm has metal, who knows, it will probably set off the buzzers on those walk through metal scanners. I just stuffed my film in my pockets in most places and got through without a snag - like Versailles and getting into Paris from London.
Bring a lead bag - I used it in the #1 pain in the *** airport on the planet : Heathrow in London. And never had any trouble. They didn't even open my bags, though it was in there, but forced me to take the film out of my camera and open all the film in my pockets. They are cheap and make lots of sense.
Don't shoot anything in the 3200 range. Some will say go ahead, but mine didn't make it to well, and it only went though two scanners. Once with a lead bag.
I have not been to Asia, but some of our members sure have - and they have some nice shots. I think you'd have a harder time shooting in New York than you might in Thailand. But I really don't know.
Bring batteries. A few sets. You'll need them most when they are least easy to find.
Bring a camera bag that is highly water resistant and closes tightly against the elements. I almost had a girl at Samy's in Los Angeles tell me that the DOmke (without water resistance) would be just fine for Christmas in Europe. Ha ha, right. It rained about 50% of the time, snowed 30%, threatened both 10%, and was gorgeous and sunny 10%.
DOn't bring a pile of lenses - sounds like you figure this already. Just one lens. . .two maybe if you do something like 28mm and 75mm. The 35 should be totally perfect if you're fearless enough to get close to the action.
Buy a camera that has the fewest options for breaking - or one that is built well enough that you can count on it surviving for a long time, under stress, and without being babied. Leica makes sense, of course. I'd say even a Nikon F camera because they are like solid rocks, but mirror boxes are troublesome. I would bring the Nikon F6 because it is supposedly very well built. But, I'd buy an M7 first.
Be fearless but intelligent. You'll see so many pictures you'll want to take, and you should just take them, and be open about it and obvious. Never let fear of being noticed scare you away - but have respect when it's due. Like a funeral or something that requires respect or which outsiders are not welcome to invade on any level, let alone with a camera. Don't mess with that.
Never walk without the camera around your neck, ready to fire. Don't bring super slow film like Velvia because it has minimal usefulness compared with faster E-6 like Provia. Try Fuji NPH - I love it. I shot some NPZ800, and it is a little too grainy for my tastes. If you are shooting with a fast lens on an accurate body - just bring some 400ISO negative or slide film, then you can stuff it in the lead bag and not worry about it. My Delta 3200 made me sweat bullets every day.
I brought a little Slik tripod, just small enough to slip in the belt loops on my camera bag, and it was easy to whip out and use within 10 seconds. You may or may not want this. I know I only needed it maybe 5 shots out of 400. BUt I am glad I had it. Not to mention, it would have made a very effective weapon against thugs. Buying a little pocket sized t-pod would make alot of sense - for shooting in bars/restaraunts, etc.
Keep everything in zipped pockets on your body. Nothing hanging off, nothing in pockets that can be reached into without first unzipping or unsnapping. Keep money in more than one place, and your passport (or whatever) in an INSIDE pocket and a copy of that in a separate place on your body.
Use UV filters on your lenses - never know when some gust of wind might decide to hurt your glass. I removed them when I knew I wanted top quality on the negative, but when it was misting rain in northern England, I am glad I had the filter on there.
OF course, don't even try going through customs without taking the film out of your camera first - and make it easy for them to search things. I held my cousin up horribly in a few places because they needed to search me hard and deep.
You never think of this, at least I didn't, but make sure to use the self timer on your camera and get some shots of yourself every now and then. They aren't that romantic or exciting now, perhaps, but they will be later on. Very much so.
