*The photo above was not taken by me. It was purchased from 123rf.com.
I have been bouncing around the world for the last 12 years and through a great deal of that I have been carrying my photography equipment with me. As proof of my experience I can show you a wall of camera bags, each purchased while looking for the best bag possible! I can also show you hours of YouTube video watching from a variety of experts telling me what to pack and what to leave behind.
I began making the typical beginner mistake and tried to carry it all. I had a massive back pack, every lens I owned along with filters, tripods and various triggers. After a few trips I decided I should see what the experts told me to do. The vast majority spoke of traveling light and so I began changing. I would take a ton of gear and leave it in the hotel with a smaller "day pack" to carry around with me.
Then I changed over to a truly light carry philosophy where I only packed one camera and a couple of very small lenses. I was light, care and fancy free. But here is the thing...I missed some shots because I did not have the right gear. Was it a massive loss? No, but I kept asking myself what the reason for my travel was.
That is the trick of it, I have discovered. You should understand what is the purpose of the trip. On most of my business trips I take nothing but my iPhone and sometimes my Rollie 35. On a trip to visit family, a simple film or digital camera with a 35mm lens usually works. Going to the beach? One camera and one lens as I do not want to be tempted to change my lens with all the wind and sand.
A family vacation? That all depends on the destination and method of travel. If we are going to be in the middle of Paris and just walk around to see the sights I will allow myself to carry a bit more. If we are going to be jumping on and off buses, trains or taxis then I prefer to go very light, one camera and a couple of lenses.
I never take more that one film and one digital camera. Ideally I select the set to be able to share lenses. My Leica M6 and my M9 are a good example. My Nikon D800 and my Nikon F3, F4 or EM is another.
I will always google the place I am going to in order to create a image list. I then see if a telephoto would be in order or if I should go wide angle. New Zealand cries out for a wide angle lens but a city like Paris calls for some street photography with a normal lens. Going to shoot sports or wildlife...telephoto it is.
Out of everything I have learned, below are the only "never break" rules.