There have been a few field gear posts going around recently, and I thought I'd contribute a few photos of myself in full field attire. (OK, I'm way behind and I wanted to post something to get myself writing for fun again.)
Hat: Either my fully-insured Tilley hat, which floats and has a hidden compartment, or a cruddy baseball cap that inevitably gets turned around backwards and makes me look really dorky, or a bandanna of some sort. My hair will frizz in any humidity, and I have about a million of those little flyaway hairs that never seem to grow out. (I will occasionally, and in the right states, wear a straw cowboy hat. It tends to get crushed whenever I pack, though, so it's looking pretty battered.)
Face: Occasionally sunburned, but mostly it just gets really freckly. And, since I don't wear makeup in the field, it always ends up looking like I have some sort of pox by the end of the trip. The desert air does nothing for my skin, probably because I'm too busy slathering sunscreen and insect repellent all over it. Sometimes I'll wear sunglasses, although it's been a struggle to find a non-dorky looking pair that I can put prescription lenses in. I'm hoping the current ones last for a while, because they were not cheap.
Neck: Always a hand lens, occasionally with a pen or mechanical pencil attached when I'm too lazy to put it back in my bag or pocket. Camera if I can't fit it in the backpack or pockets or want to keep it handy.
Top: Grubby T-shirt or sports tank, with a button-down of some sort over. Sweaters (khaki) or fleece (clean if we're going to be around civilization, grubby if not) over top, with optional raincoat. I rarely wear a vest because I haven't found one that doesn't make me look like either an escaped fisherperson or an overzealous tourist, but that could always change. Sometimes I'll spring for a safety vest if I'm going out on lava flows, for instance. (This has always struck me as slightly unnecessary, since any clothing that isn't black will stand out on basalt, but I'm all for safety.)
Pants: (Or trousers, for the overseas crowd) Zip-off hiking pants for warm weather, army surplus cargo pants for cooler weather, and my newly-acquired women's Carhartts for whatever will rip up the other two. My main requirements are that I have to be able to fit my field book into at least one of the pockets, and that there are belt loops big enough for a normal-size leather belt. (This is often a problem with the hiking pants, especially when they come with those silly clip-belts, but I can usually solve it with some creative cutting.)
Pockets: Digital camera, cell phone (sometimes), granola bars, colored pencils, pocketknife, rocks. I expect a high carrying capacity from pockets in my field pants, which is the biggest reason for the belt.
Belt: Complete with Brunton, GPS, and whatever else I couldn't fit in the pockets.
Boots: My current favorites are Asolos, although I may have to replace the most recent pair after the next big trip because I melted most of the tread off in Hawaii. Mine are orange and black, which I think is particularly appropriate for a volcanologist.
Backpack: Everything else! I'm particularly fond of the ones with holes and clips for CamelBak-type water bags - the only drawback to these is that it's hard to keep track of how much you're drinking. I always carry an extra bottle or two of water, especially if I'm in the desert. Also a first-aid kit, more snacks, extra clothing, lots of blister stuff, maps, clipboard, sample bags with rocks in them (if I haven't just thrown the rock in the pack), bug spray and sunscreen, more rocks, markers and pens, batteries, and rocks. Did I mention rocks? I'm kind of compulsive about picking stuff up.