When in the field, how do you carry your kit? Do you keep the camera attached to your tripod (monopod)?
Sometimes, when I'm out just for birding, I have stuck a single lens on the tripod, with the tripod attached to the lens collar, and slung the rig over my shoulder leaving the tripod legs extended when walking from spot to spot. But I often shoot without a tripod, so that's only my solution when using one.
Do you keep the largest lense on the camera and keep others in your pack.
Usually if I'm out shooting with a variety of lenses of smaller focal lengths, I'll start out with the largest attached to the camera...and switch as needed.
Do you keep your TC attached or only attach them when needed?
Typically I have mine attached in advance, and leave them on the lens the whole time. I'll often keep the TC on the lens even when switching the lens out for another - only on rare occasions will I remove the TC and reinstall the same lens. For me, I tend to decide if the TC will be needed, and if it will, it usually stays on.
Do you have different kits when setting up in one location versus hiking?
Definitely - I tailor the kit, the lenses I choose, and the bags or straps I use based on the shooting location and intent. I'm more prone to bring two very large birding lenses along, one attached to the camera and the other in a lens holster around my shoulder, when I'm in a wetlands or birding area with lots of level walking. If hiking or traveling uneven terrain, or in bad climates, I might leave the second long lens behind, or even occasionally go with just a shorter focal...something handier for hiking. Sometimes if the hiking is exteme and I need to keep use of my hands for climbing or pushing through narrow trails, I'll even leave the DSLR kit behind altogether and switch to my mirrorless camera and installed lens, since it's much lighter and easier to bring along hung on a belt clip holster.
I keep a variety of camera bags of various size and shape for bringing extra lenses along, depending again on the shoot and the location. I have a very small bag that can just fit a single camera body and mounted 200mm lens - nothing more. I can bring it empty when I need weather protection for the camera, or I can carry the camera and mounted lens in-hand with one additional lens in the small bag. I have a medium sized shoulder bag that can allow me to bring 2 or 3 extra lenses along, and just squeeze my camera into the bag too for weather protection...but no long lenses. I have a holster lens changer bag that can accomodate two long lenses side-by-side, so I can bring my camera with one long lens attached and the other long lens in the holster - there's always an empty holster chamber so I can quickly drop the mounted lens into the empty chamber, disconnect the body, switch over to the other lens in the other chamber and mount the camera, then pull that lens out...it lets me change long lenses on the fly without having to put anything down. And finally I have my large Kata backpack, which can accomodate a bit portion of my gear, for traveling and transporting - It can handle two camera bodies, and upwards of 11 lenses, and can fit even my 300mm F4 or 200-500mm lenses mounted on the camera body. I can squeeze in all accessories, chargers, filters, and even a netbook.
Hope that helps!
