Twilight. It's not about cute vampires. It's about blood-sucking overexposure. Bone-chilling underexposure. Palpably inadequate tonal range. A challenge that occasionally comes up in landscape photography is shooting at twilight into the setting sun. The sky tends to be blown out in that situation — the highlights are "clipped" or contain no picture data — and the foreground, in low light and shadow, is usually too dark. One answer? Extreme exposure bracketing. Exposure bracketing is the process of shooting multiple photos of the same subject and adjusting the camera's exposure settings to brighten or darken the image. We're not talking about three frames at 1/3 intervals here, but five frames separated by a full stop (one EV), or three frames at two stops.
Using these intervals, you'll be capturing the scene with exposures ranging from a quarter of the brightness to four times the brightness of your starting exposure at a given ISO. And then you can merge the files later to adjust for the great differences in light. Because it can get confusing talking about exposure compensation in relation to exposure values (EV), let's use the abbreviation eC to refer to compensation settings and back up a little to explain what EV actually is.
Technically, EV is the result of a formula that takes into account both aperture and shutter speed and expresses it in a single number, using the binary logarithm (log2): EV = log2(N²/t), where N is the aperture and t is the shutter speed. You can figure it out easily enough with a log base 2 calculator (there's one at miniwebtool.com/log-base-2-calculator/). For f/2.8 (2.8² = 2.8×2.8 = 7.84), for instance, at a shutter speed of half a second (7.84/.5= 15.68), the EV is log2(15.68) = 3.97. Let's call it 4. And frankly, that's not a great deal of help to you unless you're planning on creating an exposure chart to consult for particular lighting situations — something that the technology in your camera nowadays makes unnecessary (though slightly more important if you use a hand-held light meter).
But some folks like the math side of things, and if you want to spend an exhilarating evening (if you're mathematically excitable) or an excruciating, soul-deadening one (if you're not), the Internet has literal pages and pages of this stuff. Photography is optics. Optics is mathematics. Knock yourself out. But photography is also an art.
The reason I took the detour into the exposure value formula is to make the point that all you really need to know about exposure bracketing is that most cameras today allow you to compensate for challenging light conditions by changing the photo's exposure in parts or multiples of 1EV. In other words, you only need to attend to the relative light values of the frames rather than what they represent, bearing in mind that because aperture, shutter speed and EV are all directly related to one another, full intervals have a straightforward 1-1 relationship.
The difference between an aperture setting of f/4 and f/5.6 at ISO 100, with shutter speed constant at 1/30, is 1EV. Between a shutter speed of 1/125 and 1/250 at f/8? 1EV. And so forth. So we're not interested in the formula as much as the relative effect of changing your settings by +/- 1EV (one stop), or a fraction thereof.
The exposure compensation dials of most current DSLRs allow adjustments in one-third (.3) or two-thirds (.7) stops, in addition to single stops, two stops etc. And with auto exposure bracketing, you set the intervals, tell the camera which side of your starting exposure setting to make the changes, and then fire off a burst of three or five frames, or more.
Piece of cake. The art comes in deciding what intervals are going to cover the scene's lightest and darkest features. You want the lightest photo to illuminate all the detail in the darkest areas; you want the darkest photo to provide some picture information for the lightest areas. In fact, software like Photomatix Pro will give you a report: of your three images, say, the underexposed photo covers the brightest parts of the scene well, but the overexposed photo may not cover the darkest parts of the scene well enough, in which case you may want to include a longer exposure in the group. We'll show an example of just that with our twilight shot shortly.
Now, exposure bracketing may vary depending on your camera's make or model. I'm a Nikon guy, and my D850 has a dedicated button for bracketing (either or both of exposure and flash). The exposure bracketing options are considerable: up to nine frames at 1EV intervals, five frames at three full stops (3EV intervals), and various choices for three frames from 1/3 intervals to 3EV. In short, more than you'll likely need in any lighting situation. But even my old CoolPix B700 (an ultra-zoom "bridge" camera, not a DSLR) has exposure bracketing, though a more humble version, allowing 1/3, 2/3, or 1 full stop either side of the selected exposure compensation setting. I'd say either side of 0.0. eC, but it's possible to set the starting exposure to -1/3, say, and bracket either side of that. The curious thing about the Nikon line is that the D3500, a true DSLR, albeit an entry-level crop sensor camera, doesn't have auto exposure bracketing. You'd have to shoot three frames of the same subject, manually changing the settings between shots.
Why do we need exposure compensation, then? Aren't the technological marvels we use as photographers today capable of getting it right the first time, every time? Well, no. The cameras are incredibly sophisticated, true, but some situations can still trick the sensors into giving us inadequate readings, and some conditions are simply too extreme to be captured satisfactorily in a single shot. Snow and white sand, for instance, throw off the camera's judgment. It overcompensates and underexposes the image. With snow, counter-intuitively, we need to increase the exposure by 1/3 or 2/3 to adjust for the faulty reading. To compensate for the over-compensation, if you like. Sometimes, we just want to hedge our bets. Maybe the lighter image will be best, maybe the darker. With extreme conditions, where the range of light is too great — well, we get back to our twilight evening.
It's a rural road in northern Colorado, horse properties and houses on one side, with their roosters and vegetable gardens, cornfields on the other. Traffic is light: a few commuters are coming home. There's an old dairy down the road, family owned, well-established, and given new life by partnering with the Australian yogurt company Noosa, which shares the site now. A black pick-up heads north to the feedlot. Black Angus cattle dot the hillside, a skunk follows the shoulder, along the field's edge; mule deer watch from under shade trees. It's a warm mid-summer evening, dark earlier now than at the solstice.
I usually like to shoot the little birdhouse on the fencepost in winter, under steel-blue skies. The corn stubble is patched with snow then, and the incongruous wooden facade of the nest box rises above the austere geometry of the landscape. But the corn is high now, close to harvest. The picture elements are still spare — fence, corn, sky — but looking west, with the sun near setting, the corn stalks lie in deep shadow, the horizon luminous. What are the choices? I'm on aperture priority, ISO set at 1250 and auto sensitivity off. I don't want the ISO to change between shots, just the shutter speed. I can take five frames at 1EV intervals, but I elect instead to shoot three frames at two-stop intervals. The reason? There's enough of a breeze that any movement of the leaves or the tassels behind the fencepost will need to be aligned when the frames are merged later, and the more frames there are, the longer the total shooting time will be, and the greater the chance of movement. Even with a tripod, then, the final image may show some haloing or ghosting where alignment isn't exact. So, faster is better.
When it comes to merging the exposures later, I also have choices. We could import the three images into Adobe's Lightroom, select all, and then choose Photo > Photo Merge > HDR Merge. In Photoshop, on the other hand, we go to the File menu, then Automate > Merge to HDR Pro. But I favor Photomatix Pro for its controls and the smoothness of the result. Result in hand, you'll still want to make adjustments, reduce noise, dodge or burn here or there, convert to grayscale perhaps — but you should have an image with plenty of picture data and tonal range to work with, particularly in bringing out the sky and clouds. As it turned out, Photomatix Pro wasn't entirely happy with me: it didn't think the lightest photo did a good enough job of revealing the darker details, so I added as fourth image, more overexposed, and adjusted the intervals so I had two frames with 2EV between them on the light side of my starting exposure (0.0 eC here), and only one on the darker side. It did the job just fine.
Taking the actual photos on the dairy road, with a little preparation and experience, was the work of a few minutes. It was still warm when I left, but the light on the cornfields had dimmed. A skunk sniffed at my shoes. Bats took to the air. Sia popped out from between head-high stalks and started singing "Dusk Till Dawn". I could have imagined that last one. Rural night plays tricks with the senses. Time to get home and get merging.
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Art students, when I was at school, sometimes joked that a sculpture was something you bumped into when you stepped back to look at a painting. They were usually painters themselves, of course, teasing classmates who sculpted, or, more rarely, trying to make a serious argument for one medium over the other. Art historians repeat the joke, but to do the opposite: to point out how unfairly Monet is favored over Henry Moore, or Pollock over Paolozzi, or for that matter Picasso the painter over Picasso the sculptor.
We have biases — as individuals, and as much as we contribute to popular taste: flowers over fungi, raptors over robins. Photographers, too, play favorites. For every artful paw-paw flower there are a thousand photos of great grey owls or Alaskan grizzlies. And without deprecating either, if you're shooting a spectacular carnivore at twelve frames a second, sooner or later you're going to capture it doing something spectacular.
Flower photographers work harder, if only because mediocrity is easily at hand. The "oh, that's nice" down-shot of a sunny daffodil trumpet, the corolla of the black-eyed Susan, a purple hyacinth that catches the eye as you're about to get in the car, on the way to something more important. Many of us bump into floral portraiture while we're trying to look at something else.
So it was on July the 4th this year. I had set out early up the canyon in the hope of beating holiday traffic, thinking it might be a good idea to hike the five miles or so to Blue Lake, a small subalpine gem at the base of Cameron Peak in the Rawah Wilderness of Colorado. Reports had said the snow was off the trail above 10,500ft and the weather was promising: hot later, but mild enough at seven or eight a.m. I started out at about that time, the parking lot near the Laramie Road already filling up. It wasn't ideal. By eleven, when I reached the top, the sun would be high and fierce, broadly illuminating the north slope of the bowl, its rock cairn, and the bleached krumholtz, but washing out the lake itself and its southern prospect. I would be back at the car before evening lent a moody magic to the tree-line shore. Staying overnight where Fall Creek crossed the trail wasn't an option this weekend.
But there are always opportunities. Some of the best professional photographers favor conditions others consider counter-intuitive. Annie Leibovitz welcomes overcast skies. She knows how to handle flat light, even with minimal fills, reflectors and strobes, and still get the dramatic tarnished effects of her Vanity Fair shoots. David was telling me earlier in the week about a flower photographer he admired who preferred to shoot either side of noon, between ten and two, and more often than not, directly into the sun. Conventional wisdom — the sun at your back, a strong light source — benefits conventional photographers. Artists and innovators tend to make their own wisdom. And some know when to change tack, and take a different direction.
As it happened, my original plans were moot by the time I'd reached the lake. Along the way, in the meadows either side, among nurse logs and wetland seep, what seemed like the full gamut of Colorado wildflowers was out: Mertensia, Arnica, columbine, wild strawberries, osha, glacier lily, mountain parsley, marsh marigold. A quick online search will list some of these flowers as appearing until June, and I hadn't expected nearly so many, but I had forgotten the elevation. Time slows in the mountains. Five thousand feet below, that may have been true, but it was still snowmelt here, despite the Independence Day festivities in town, the illicit flash-bang neighborhood fireworks, the smell of grilling from down in the cove.
And so the landscape session, the lake session, became in impromptu flower shoot. As I'd thought, the subalpine bowl at the top of the trail was warming fast, and I stayed only a short time, taking photographs of the creek that fed the north end of the lake, the steep switchback up to the pass, stubborn ribbons of snow on the west shore. Even then, yellow avalanche lilies occupy the foreground. The area up to 11,000 feet in this spot has a curious transient quality. After five miles of hiking and five hours travel time, I rarely stay more than a few minutes (camping is also prohibited in a quarter-mile zone around Blue Lake and Hang Lake to ease pressure on the habitat), and I'm not alone in that. Most of the hikers I passed, or those slipping past me as I stopped to shoot, paused as briefly, turned, and began the trek back to the trailhead.
The cliche is true on the trail, as it is in life. The journey matters here, and not just the destination. For visitors feeling the heat or the altitude, the cool of the creekside is more comforting than exposed tree-line, and in the Rawahs, a raven or water ouzel might make an appearance. For the photographer, the cover of lodgepole pine, spruce or fir and the filtered light through the tree canopy produce startling effects. I've been tempted, as I was with the picture of Mertensia lanceolata here, to desaturate the image a little, thinking no one would believe the intense royal blues and magenta were natural. A lavender and white columbine (Aquilegia caerules), the state flower, had a similar glow in the undergrowth. Pausing, stepping back, benefits the photographer as much as the footsore hiker. And when we bump into wildflowers while we're on our way to look at something else, it's usually best to turn and take the hint.
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Pawnee ButtesPawnee National Grassland, June 28, 2020; photo: Vyvyan Brunst
It's almost too early, even for the sun, but David is an early riser. Somewhere in a kitchen in Fort Collins, he has fed the dogs, made coffee, packed his Fujifilm X-T2 into the Subaru, and is preparing to drive east to the plains. It was my idea, a brief photo session on the weekend in Colorado's Pawnee National Grassland, but I am used to him being a step or two ahead of me. He's the better hiker, a veteran of five thru-hikes on the 500-mile Colorado Trail and many more rugged miles in other states: he travels light and fast, advises Forest Service volunteers on gear, and mentors many others. When we began our photography business we called it Ultralight Images, with a nod to the wilderness trail as well as to that indispensable element of all photography, light. It's in the word. The Greek φωτός (phōtos), light, and γραφή (graphé), drawing. Drawing, or writing, with light. We do both, and plan to do both, to tell stories with light, lightly and well.
There is little traffic as I head out: tanker trucks and night-shift nurses heading home. I pull down the driver-side visor and swing the Jeep onto Highway 14, where it will stay for the full 42 miles to the Crow Valley Campground. Older men — mature men, experienced men, my wife would object; old men is ageist — mature men are sometimes given to quixotic adventures. Cervantes's hero himself was fifty-something, well advanced at a time when life expectancy was thirty-five, but he had the good sense to also set out with a companion.
The landscape quickly turns rural. It's the nature of the Front Range: with the Rockies at your back, and the college town at its feet, the Great Plains begin only steps away. Greeley, off to the south, was founded as a utopian agricultural community a few years after the Civil War ended, and it grew out of its pioneer roots into sugar beets and cattle — like many pioneers, enterprising, even experimental, in some ways; deeply conservative in others. I used to drive Highway 14 every weekday morning on exactly the same route I was driving this morning, to work at Greeley's sparkling performing arts center, one of the largest in the state. But now, instead of taking a right onto the 85 at Ault, I keep the Jeep pointed east, into the rising sun.
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David W. FanningAt Pawnee National Grassland, June 28, 2020; photo: Vyvyan Brunst
In a photograph from our session, David stands on a stretch of shortgrass prairie, within easy sight of the buttes that push up like ships' turrets, and looks back down a dry wash, along the way we came. It is late June and the greening rains of the spring are done. Now, the pattern is still-cool nights and building heat — today will reach 91 degrees Fahrenheit. By afternoon, thunderheads have stacked themselves over the northeast and north-central parts of the state, and lightning storms will slash at the chalk bluffs, the red-chestnut and the bleached-sand, the buffalo grass and the blue grama, scattering occasional jackrabbits and pronghorn antelope. But it is still mid-morning. The clouds drift across out of the southeast, stratocumulus, low, broken and benign for now, shielding us from the intense glare of early summer. David is dressed practically, in shorts and short sleeves. There is no high brush to navigate, nothing to tear up the legs, just a grove of Rocky Mountain juniper in the arroyo, where flash floods have drained off the high ground, and prickly poppy, Yucca glauca, pricklypear cactus, easily dodged.
He seems to be gauging the light, watching shadows splash artfully on exposed slopes. Hidden to the viewer is a camera held close to his chest. We have come here to add to our landscape portfolios, a collection for David that includes stunning shots of the Weminuche Wilderness, an area bisected by the CT that covers more than twice the acreage of the vast national prairie we are on. He shoots casually, between snatches of conversation, but the ground in the photo seems to pitch awkwardly, like the deck of an ocean liner in unsettled seas, and David is angled forward as though balancing himself against the roll of the ship. In the journals of the Corps of Discovery, recording the three-year expedition of Meriwether Lewis and William Clark, Lewis wrote that sometimes on the plains it seemed like you were out of sight of land. When I repeat the observation, folks tend to look at me oddly. But it's true for everyone who loves the peace of the prairie, its endless rolling expanse, its uncertainty, even its frightening implacability. What is out there, and what will it give or take from us?
The sides of the ravine at the picture's bottom right, at the end of David's gaze, are lit up in a buttery sheen. He stands in patchy shadow, though, and when I processed the image, I couldn't help thinking how the weather seemed to register the dramatic and shifting changes we've seen over the last four months. Even today, the two of us are learning how to navigate a start-up business under the shared menace of a global pandemic. It affects our hike. There are no hugs or handshakes; we keep a reasonable distance — easy enough in the remote grassland with only a red-winged blackbird, meadowlark, or lark bunting to interrupt.
Later, stopping at a roadside pioneer cemetery (a compelling, otherworldly place for photographers), we lean against our cars and talk over the divide, planning a business, talking about weddings, charity events, wildlife assignments, at a time when many businesses are struggling. We have logged too many miles on the trail, like the Corps of Discovery, like Quixote and his neighbor, to be calmed or put off by the weather. It rarely happens as you expect. A good hiker is a good planner, but an experienced hiker adapts, knowing that there is almost always something extraordinary around the corner. Images to keep. Stories to tell.
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