Recharging these high-voltage puppies in winter can be done, but it’s complicated. Begin with a strong solar panel, such as the GOALØ Nomad 27M Solar Panel, Brunton 14-volt SolarRoll or Solar Blazt Feather 20 or Feather 30 from HumanEdgeTech, a company specializing in expedition electronics. Then you need HumanEdgeTech’s battery, the HET Power 50. The third ingredient is a good inverter, like the Tripp Lite 150. You connect the inverter to the HET battery, plug the standard EN-EL4a charger into the inverter, then charge the EN-EL4a off the HET battery. When the HET battery runs out of power, you can recharge it with the solar panel, as long as the sun isn’t too low. But unless you’re also using the solar panel to charge a lot of other electronics, it’s easier (and weighs less) just to bring enough EN-EL4as.
Tripods. Many nature photographers prefer a carbon-fiber tripod in the cold, but the legs of my carbon-fiber tripods stick in the cold, so while I love them in summer, for winter use I revert to an aluminum model, the Gitzo GT2331. In subzero temperatures, the hard plastic insulation on the upper legs of my aluminum Gitzo feels almost as cold as bare metal, so I further insulate them with pipe foam.
Really Right Stuff L-Bracket
Ballheads. Below about -20° F, even a good ballhead becomes stiff. With patience it can be moved, but it’s easier to adjust the tripod legs or lens collar. My camera also wears a Really Right Stuff L-Bracket, so I don’t have to wrestle the ballhead to compose vertically.
Storage. I don’t bring storage drives on winter expeditions, but I do carry lots of SanDisk Extreme flash cards; 100 GB of flash cards costs about $700, lasts for years and usually is enough for several weeks. Kingston, Lexar and PNY also make durable memory cards that will last you for years.
San Disk Extreme Pro
Bright Colors. When photographing people in a winter environment, avoid blue or green jackets. Red and yellow are the only way to go. (Trendy colors, like neon green, go out of fashion quickly; in a few years, they look as dated as striped bell-bottoms and four-inch sideburns.) Red works better in sunny weather; yellow pops on overcast days. I have jackets that I give or loan to the people I travel with. I also carry colorful fleece and even a red undershirt so bright clothing is available on warmer days.
Mountain Hardwear Swift Jacket
Wristlets. I used to wear wool wristlets, like those used by the British Army in World War II, under my gloves. (Google British Army wristlets to see what they look like.) They allow me to use thinner gloves and protect the bare wrist area. Eventually, I converted to 300-weight fleece instead of wool. Fleece lasts longer and doesn’t shrink. Just sew a rectangle of fleece into a tube that extends halfway up your forearm and covers the back of your hand, but not your palm. Cut a hole for the thumb and sew two small loops for your index and little fingers. Wristlets add about half a layer of warmth and can fit under any glove.
Glove Choice. Whenever I go into an outdoor store, I try on gloves like my wife tries on shoes in shoe stores—for the fun of it. If one seems promising, I buy a pair to test in the cold. The fingers have to be exactly the right length: Too long, and they flop like clown shoes when you try to press the shutter or work the controls; too short, and the fingers get cold. The gloves can’t be downhill ski gloves—they’re too thick. Ideal is a fleece model, like The North Face Denali glove or Auclair Sport Fleece gloves, that resists wind without actually being Windstopper®. Windstopper® fabric gets boardy in the cold.