Most outdoor places I go I take a backpack with all my gear, three bottles of water, and two dry pairs of socks. Usually I carry a tripod as well. I really don’t see much benefit in not carrying two or three lenses I don’t use in that configuration; compared to the water, they’re pretty light. Sometimes I don’t use the tripod, but I end up needing it as a balance aid often enough that it’s worth carrying even when I doubt I’ll use it photographically. Plus I figure any extra weight is extra calories burned.

When I go somewhere I can dump the backpack, I take it with me, since there’s no reason not to. The tripod lives in the trunk of my car if I’m not carrying it somewhere, so it’s usually available.

If I’m going somewhere with a specific purpose, I tend not to carry a bag at all. Either I’ll glue one lens to the camera and use it all day, or I’ll put the pouch that came with the 135L on my belt, and bring one medium-sized lens plus one or both of the Nifty Fifty and Zuiko 24mm f/2.8, which are pocketable. I love the Zuiko in particular for the convenience of its size.