How to photograph Lightning

Lightning Photography
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"Gee, Boss, this is a tough assignment."

"OK, Jones, you want to show me what you can do; I've got just the assignment for you. Your subject is only visible for about 50 milliseconds and may appear anywhere within a 400 square mile area. You won't know when it will appear, either, and it will only show up one time. I want it shot on transparency film, of course, so exposure will be critical and there'll be no chance to bracket. The subject will have an EV range of about 8 stops, depending on several variables, and there will be no time to read it with a light meter. One more thing -- it may kill you."

What the boss is asking Jones to shoot is my favorite subject -- Lightning. In many ways it is as difficult to shoot as it is awesome to observe. Any way you approach it, you can count on using a lot of film, spending a lot of hours, and driving many miles before you begin to have a decent portfolio. You can also count on having more than a few hair-raising experiences along the way, most of which will not be due to the electrical phenomena you are stalking.

Unlike most subjects, the more ambient light that exists, the harder it is to capture a good lightning shot. Out in the middle of the boonies on a dark, moonless night is the easiest place to bag a good lightning. It can also be the scariest place, too. Out in the desert where I shoot most of my work, the night is full of all sorts of critters and pitfalls. The more of them you encounter in subsequent sojourns, the more your imagination works overtime in conjuring up things that can confront you the next time you venture out into the dark desert.

It's a good idea to quit reading the likes of E.A. Poe, H.P. Lovecraft, and Steven King. Also, local news of any sort, print or video is best avoided due to its propensity for showing bodies discovered in the desert. I find that it's good to take along a companion to ward of such night spooks. As for your companion, pick a stout lad that is well versed in CPR and convince them that you don't have any communicable diseases. You may want to leave them inside an all-steel car to prevent a lightning strike from getting him at the same time it does you, a not uncommon occurrence which we'll discuss when we get to flashovers and step voltages.

So, you've picked a dark, moonless night in the middle of the thunderstorm season and made your way to an uninhabited area where your photo will go unspoiled by the lights from dwellings or passing cars. Only an occasional airplane overhead could screw things up, here; assuming that you haven't tripped a Border Patrol sensor and bring them down upon you. You've done your meteorological homework and placed yourself along a common storm path. You've arrived before dark so that you can determine the best spot to shoot from, unobstructed by ridges, fences, powerlines or other objects which would go unnoticed in the dark but stick out like a sore thumb when backlighted by a good lightning strike.

Of course there are only two general classes of places where you can avoid all the undesirable features in the landscape and showcase your lightning as it arcs from the cloud to where it makes ground contact: on top of a hill or in the middle of a large, flat field. Try to have your car and CPR-trained companion parked close by when in such places because open areas and hilltops are our subject's favorite killing grounds.

Now that you've attained the perfect perspective from which to shoot, you need to get to the technical end of things. A tripod or some other form of rock-steady camera support is necessary. If you've planted yourself in the path of an on-coming storm (a great place to catch those spectacular positive strokes that often form on the leading edge) you can count on winds between 25 and 65 mph. No puny aluminum tripod is going to stand up to that kind of action.

I often use a huge old Majestic studio tripod when working in high winds. It weighs nearly 30 pounds and extends to over nine feet. I've had many people express concern over metal tripods and suggest wooden or even plastic ones. If safety is your concern, you shouldn't be on top of a hill in a thunderstorm to begin with. Such a lightweight, non-metallic tripod won't do the job and it's not likely to reduce your chance of getting struck much, anyway.

Another myth to debunk is the bit about putting your camera inside a plastic bag with only the end of the lens sticking out. Short of shrink wrapping it, the plastic bag thing doesn't work in high winds. The bag flaps like a demasted sail and shakes your camera in the process, ruining your shot. Use a lens hood and hunker down over your equipment, letting your body shield it from the rain. This will work for almost anything other than rain blowing at you head-on.

When you are done, wipe off your camera in the field and give it a thorough dry-out when you get home. I sometimes put mine in the oven at a low temperature and then put them away with bags of desiccant if they've had a light soaking. Don't overdo the oven thing -- too hot or for too long and you'll dry out internal lubrication in the cameras or lenses. If they get really wet, take them to a good camera repairman right away. Can't imagine getting your gear that wet? What the heck, if you can risk getting your feet blown off by a lightning strike, your camera ought to have to take a chance on a little mildew.

You could always use weather-resistant cameras, like the Canon EOS 1, or underwater gear like the Nikonos. Better yet, get an old mechanical body that you can afford to lose if it gets drowned. I use Canon FTbs. They're still relatively cheap, they work without batteries, the Quick-Load feature is a real blessing when changing film in the dark, they've got a mirror-lock-up and they'll take a lot of abuse before they quit on you. Best of all, however, is that they don't eat up expensive batteries like the new electronic cameras will on time exposures. You want to waste your money on film, not batteries when shooting lightning.

OK, now you're in position and well equipped. It's dark, but you've remembered to bring a small penlight and your reading glasses so you can see the little numbers on the controls of the camera and lens. What do you set them at? That depends on a number of variables. The first is your film speed. I suggest settling on one film; I like Kodachrome 25. The slow speed seems to work well in all light conditions, reciprocity failure is not a significant problem, and for daylight or sunset lightning shots it gives you a little longer exposure time and that increases your odds of getting something worthwhile.

So you've got fresh roll of KM-135-36 in your old FTb. Next thing is to determine f-stop because you're going to set the shutter on bulb for a time exposure. F-stop becomes a little tricky. The farther away the lightning bolt is, the more you have to open up. This is not only because light falls off inversely with the square of distance, but because of atmospheric conditions ranging from normal haze to heavy downpour.

Most beginning lightning photographers like to start out a long way from their subject and often use a telephoto lens so the bolt won't look too puny. Generally speaking, the longer your focal length, the more you open up. If you're using a 100-200mm tele lens, try f4 or f5.6 depending on how hot the stuff looks an how much rain you're shooting through. If you're braver and filling the viewfinder with bolts through a 50mm lens, f8 will probably be a good starting point.

Remember, though, that positive strokes (rare, only account for maybe 10 percent of all lightning) are three times hotter than negative strokes and that can throw off your exposure computations. Also, the number of return strokes (the average is about five but there can be upwards of twenty at times) will also affect the amount of light reaching your film emulsion, so if the stokes flicker a longer than normal time, or look particularly bright, stop down accordingly.

By the time you start using your 17mm or fisheye lenses to get the entire lightning, you're in real close and you may need to go down to an f11. You also want to make sure that your medical and life insurance are paid up, too. It's within a quarter of a mile, now, and you should reconsider where you are and what you're doing. Lightning photography is very seductive and after you survive your first few encounters with the stuff you tend to get braver. Never forget what it can do to you or the various ways it can do it.

Lightning injures and kills in three basic ways. There is the direct strike, which contrary to common thinking, is actually kind of rare. People who take direct hits very rarely survive and what's left of them is a mess. A direct hit will blow your feet off, turn your organs to jelly and permanently scramble your brain like so many semi-conductors. My companion in the car has specific instructions in the event that I take a direct hit and survive. He is to step on my throat.

More common is the side-flash. This occurs when you are doing one of those things that you're told not to do, such as standing under a lone tree, beside a wire fence, under a powerline, beside a metal object, etc. The lightning strikes the object and flashes over to you. Part of the current may go to ground through you and part through the object taking the direct strike. How much goes through you and where it enters and exits your body will largely determine the extent and nature of your injuries. In all likelihood it will stop your heart. Time for the CPR-certified companion in the car.

Next is the little-known phenomena of step voltage. When lightning strikes the ground, the electric charge radiates outward from the point of contact. The ground acts as an insulator, so as the current passes through the earth, the charge is diminished. The more earth it travels through, the more it is reduced. This results in more or less concentric zones of differing potential. If one foot happens to be standing on one voltage potential and the other foot on a different potential, the current will run through your body, once again probably stopping your heart. When you hear of herds of cattle or sheep killed by lighting, it was probably step voltage that got them. If there is a lesson here, it might be to keep your feet together, although it is difficult to stand against the high winds of a thunderstorm that way.

By now you're probably thinking, "Why not shoot from the car?" Those high winds are the reason. The car shakes in the wind, even if you and your companion could avoid moving during the time exposure. In a perfectly black environment with no side or backflashes lighting up the foreground, you might get by with it. Add a single point of light anywhere within the lens' field of view and your image is marred by the movement. However, these can be corrected, later.

There are places which provide shelter from most of the wind and rain, and may even provide some protection from the lightning. Tall buildings or parking garages with metal structural framework are theoretically pretty safe. If you're interested in urban foregrounds in your shots, they should help. Smaller isolated shelters are a different story. Although lightning frequently does not strike the tallest object in the vicinity, it often does and your isolated, poorly grounded shelter is likely the tallest thing around. Most picnic shelters are good for protection from the sun, only. They're likely places to get a flashover in a thunderstorm, though.

Even if you luck out and that old metal barn is well-grounded, a strike to its skin will ring your bell pretty good. It will play hob with your hearing, possibly causing permanent losses and will leave an after-image on your retinas for many hours. Other hazards associated with isolated shelters out in the boonies are the other critters you are likely to encounter there. Where I live, these include transients, dope dealers, alien smugglers, couples doing what couples do in dark places, and non-humans such as snakes, feral dogs, wild pigs, birds that seem to delight in flapping off from behind you, and a wide variety of biting bugs, some of which may be venomous.

During those rare moments when you have successfully outguessed the storm and find yourself free of the rain, you will tend to wander about, trying to get that perfect spot to shoot from. In such situations you need to be concerned with things like open wells or mine shafts, barbed wire fences, all plants with thorns, steel game traps, large packrat holes (which always seem filled with cactus buds, red ants and at least one snake looking for a quick take-out order of packrat parts. There is also livestock on the open range, and lever-gun-toting ranchers who will wonder what you are doing out there among their cattle at night.

Many of these hazards can be avoided by the simple expedient of graduating to the next level of lightning photography -- daylight and twilight shooting. The bolts will not show up in as fine a detail as they do against a pitch black sky. The branching will only be seen when backed by storm clouds. Worst of all, your success rate in capturing a bolt goes way down. You can shoot a dozen rolls of film and not get a single usable shot. The reason is simple; you have to expose for ambient light conditions and this reduces you to several seconds at best instead of the virtually unlimited time exposures in the dark.

The best way to get a daytime shot is to find a really hot storm, watch where strikes are frequent, count the seconds between strikes, and use a motor drive, starting a couple seconds before you have counted down to your average interval between strikes. Do that often enough and if you are also lucky you will begin getting some daytime strikes. If you are tempted to stop down to something like a f22, remember that anything moving in the foreground will blur as will the clouds. Also, the lightning channel may appear less distinct.

If you are really fast on the old cable release, you may even try to catch a return stroke upon seeing the initial flash. The typical stroke lasts some ten milliseconds, so if you've got a hot storm with perhaps ten or more return strokes per flash -- and you're really quick -- you may get one or more of the later return strokes. Only the first stroke features the delicate and complex branching, however, so your shot will record less than your eye observed when viewing the scene.

That's the long of it. The short of it is: chase a lot of storms, shoot a lot of film, and hope you get lucky. Even if you never get that elusive shot on film, what you experience in the attempt will be worth the effort and expense. I'd advise Jones to think about that before turning down the assignment.