Escape from Yosemite

Gary Hart Photography: Fresh Snow, El Capitan, Yosemite

Fresh Snow, El Capitan, Yosemite

Cold, wet, exhausted, and ecstatic after a day-and-half of photographing Yosemite Valley glazed with new snow, my brother and I were ready to go home and count our treasures. Gingerly following my headlights down icy Highway 140, I rounded a bend a couple of miles downhill from the Arch Rock entrance station and found my path blocked by an iron gate spanning the road and securely padlocked in place. I knew the park had been closed earlier, but we had been told by the front desk at Yosemite Valley Lodge that 140 had opened hours ago. I glanced at the steep hillside abutting the road and wondered if my Outback could somehow make it around the gate, and quickly discarded the thought. That I even considered it at all was an indication of how desperate I was to go home.

We’d arrived in the park Monday afternoon, got a room at the lodge, and hunkered down against the incoming storm. What had been forecast to be 3-5 inches of overnight snow had just been upgraded to 12-16 inches, so we knew we’d wake Tuesday morning to something exceptional. A peek through the curtains in the predawn darkness confirmed a world of white, with the snow still falling hard. A check of the Yosemite road conditions hotline confirmed it: not only were all park entrances closed, all roads in Yosemite Valley were closed.

I trudged through the snow in the twilight to survey the photography potential near the lodge and found the view of Yosemite Falls completely obscured by clouds. The cafeteria was open, but serving nothing because the employees couldn’t make it to work. At the adjacent Starbucks I found only two people had been able to negotiate the snowy darkness to get to work—it turned out to be the Starbucks manager and his wife, a non-employee drafted into action and put on the front line.

On my way back to my room I swung by the parking lot and checked my car. About the time I identified the correct white lump, Yosemite Falls made an appearance and I hustled back to the room for my gear. But by the time I got there it had been swallowed by clouds.

My brother and I spent most of the rest of the morning watching the skies, waiting for the views of Yosemite Falls or Half Dome to clear enough to photograph, or simply for the snow to slow enough to allow us to photograph some of the closer views. We the snowfall abated late morning, we ventured out into the elements and forged a trail through the snow to the bridge beneath Yosemite Falls, because any photography is better than no photography.\

Shortly after returning to the room we got a call from the front desk telling us outbound Highway 140 had reopened. We had no plans to evacuate, but I took this as a signal that the valley roads would be open too (otherwise, what use would there be to open 140). So we dug out my Outback and hit the road. With snow still falling, the next few hours were spent circling Yosemite Valley, stopping occasionally when a view appeared, waiting for the clearing that had been promised for late afternoon.

When the storm broke, it broke fast. Blue sky appeared and spread quickly and we move around with much more urgency, hitting as many locations as possible while the snow remained on the trees and before the clouds disappeared completely. Most of the views I chose required battling our way through several feet of fresh, wet snow, an exhausting exercise almost always rewarded with a spectacular view. Pristine snow signaled that we were the first people at every spot we visited. In hindsight that should have been a clue that the park was more shut-down than we realized, but we were too excited by the sights for rational thought.

By the time we got to the day’s final location, the clouds had all but vacated the sky. A thin skin of ice obscured the reflection I’d hoped for, so I went exploring and found this view of El Capitan framed by snow-dipped shrubs. A small cloud hovered on El Capitan’s summit, reflecting a faint pink courtesy of the sun’s last rays. Framing the scene with my Sony 12-24 (on my Sony a7RIII), I widened all the way out to 12mm and moved to within a couple of feet of the shrubs to include as much snowy foreground as possible. A perfect cap to a memorable day.

But now I found myself standing in the middle of Highway 140, jiggling the padlock on the gate to make sure it was really locked, scanning the shoulder for escape routes, and wondering if I was going to make it not only home, but to the Bay Area for a talk I was scheduled to give the following day. I had no phone number that would connect to a human at that hour, and no cell signal with which to do it anyway.

Just about the time I was about to return to my car and admit defeat, a pair of headlights rounded the curve. But instead of pulling up behind us, the truck drove around my car and pulled right up to the gate. This wasn’t a tourist who had missed the same memo I had missed, it was a large work truck filled with maintenance workers returning to the yard after a long day in the park. Soon the driver’s door opened out popped the driver, fumbling with a lump of keys. I couldn’t believe my luck when the gate swung open, but I darted through before he could change his mind (or tell me that he didn’t have the authority to let anyone exit). Without slowing I waved my thanks and motored past him, heading home.


Yosemite Winter Scenes

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Alone in Yosemite

Gary Hart Photography: Clearing Storm Reflection, El Capitan, Yosemite

Clearing Storm Reflection, El Capitan, Yosemite
Sony a7R III
Sony 12-24 f/4 G
1/125 second
F/10
ISO 100

Last winter I spent a glorious day by myself in Yosemite Valley, photographing the vestiges of an overnight snowstorm. Inbound to the park the evening before, a continuous strand of outbound headlights reminded me how different a photographer’s priorities are from the general public’s. For a nature photographer, the best time to be outside seems to be everyone else’s worst time to be outside, but we know that before breakfast, at dinnertime, after dark, and wild weather are when all the best pictures seem to happen.

I arrived in Yosemite Valley with just enough light to see El Capitan and Half Dome engulfed in heavy clouds that hinted at what was in store—but so far no snow. With a storm imminent, I had no problem getting a room at a significant discount, virtually unheard of on a typical Yosemite evening. A light mist started after dinner, and I fell asleep to the sound of raindrops tapping leaves outside my window. The next morning I woke before my alarm and lay still, listening in the darkness to the unmistakable silence of falling snow.

Dressing quickly, I opened the door to six inches of untouched snow. In the parking lot I tried to determine which white lump was my Outback, repeatedly punching the lock button on my key fob and following my ears to the lump that chirped back. A little digging confirmed my discovery, and after a few more minutes of excavation I was able to to ease out of my parking space, carving the first tracks into what was probably the road (fingers crossed).

The clouds that had deposited all this powder seemed be trying to squeeze out every possible flake, but they seemed exhausted from their overnight effort and my wipers had no problem keeping up. When the final flake fell a little before 9:00, I was traipsing through drifts near El Capitan Meadow. Patches of blue sky overhead told me it wouldn’t be long before the trees were shedding snow in clumps, so I headed quickly to a favorite spot by the Merced River, hoping for a reflection while the world remained white.

The Merced here was so still and clear that I had to look twice to be sure there really was water in the river. The reflection on the far side was exactly what I had in mind, but the corrugated riverbed on my side was an unexpected complement that wonderfully matched the herringbone clouds above. In the days before my Sony 12-24 lens, I wouldn’t have been able to include all of El Capitan and its reflection in a horizontal frame, but 12mm gave me room to spare (I’m still startled at times by how big the difference is between 16mm and 12mm).

I got lots pictures that make me happy that day, but even more than the pictures, I think I enjoyed the rare opportunity to feel alone in Yosemite for a few hours. The park wasn’t empty, but between the scarcity of people, the reluctance of those who were there to venture onto the roads, and the sound-deadening effect of powdery snow, I had no trouble pretending.

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Yosemite Winter Reflections

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He Ain’t Heavy,…

… He’s My Sony 12-24 f/4 G

Gary Hart Photography: Storm Clouds, El Capitan, Yosemite

Snowstorm Reflection, El Capitan, Yosemite
Sony a7R III
Sony 12-24 f/4 G
1/50 second
F/10
ISO 100

(With apologies to The Hollies.)

The road is long, with many a winding turn…

But that’s no excuse to cut corners. Probably the question I am most asked on location is some variation of, “What lens should I use?” While I’m always happy to answer questions, this one always makes me cringe because the implicit question is, “Which lenses can I leave behind?”

What many photographers fail to realize is that the “proper” lens is determined by the photographer, not by the scene. While there is often a consensus on the primary composition at a location, that usually only means the first composition everyone sees. But if your goal is to capture something unique, those are just the compositions to avoid. And as every photographer knows, the best way to guarantee you’ll need a lens is to not pack it. I’m not suggesting that you lug Hermione’s purse to every shoot—just try to remember that your images will last far longer than your discomfort.

In my Canon life, my personal rule of thumb was to always carry lenses that cover 16-200mm, regardless of the scene, then add “specialty” lenses as my plans dictated: macro for wildflowers, fast and wide prime for night, and super telephoto for a moon. That meant the 16-35, 24-105, and 70-200 were permanent residents of my Canon bag, and my 100-400, 100 macro, or wide and fast prime came along when I needed them.

Shooting Sony mirrorless, with its more compact bodies and lenses, I now carry a much wider focal in a lighter camera bag. My new baseline (always with me) lens lineup is the Sony 12-24 G, 24-105  G, and 100-400 GM, plus the Sony 2x teleconverter. My macro and night lenses still stay behind (but they’re usually in the car), but in my bag I always have lenses to cover 12-800mm, a significant advantage over my Canon 16-200 configuration.

It’s kind of a cliché in photography to say “It’s the photographer, not the equipment.” And as much as I agree in principle, sometimes the equipment does help. Wherever I am, I regularly find compositions beyond 200mm, compositions I never would have considered before. And the 12-24 lens has enabled me to approach familiar scenes with a completely fresh eye.

A recent example came on a snowy day in Yosemite early last month. Moving fast to keep up with the rapidly changing clouds and light, I stopped at El Capitan Bridge, directly beneath El Capitan. Having shot this scene for years (decades), I was quite familiar with the perspective. So wide is the top-to-bottom, left-to-right view of El Capitan here, even at 16mm I’ve always had to choose between all of El Capitan or all of the reflection, never both. I never dreamed I’d be able to get El Capitan and its reflection in a single frame. But guess what….

Standing above the river near the south side of the bridge, I framed up a vertical composition and saw that at 12mm I could indeed fit El Capitan and the reflection, top to bottom. Whoa. With very little margin for error on any side of the frame, I moved around a bit to get the scene balanced, eventually framing the right side with the snowy trees lining the Merced. My elevated perch above the river allowed me to shoot straight ahead (no up or down tilt of the camera) and avoid the extreme skewing of the trees that’s so common at wide focal lengths.

12mm provides so much depth of field that I could focus anywhere in the scene and get front-to-back sharpness; the flat light made exposure similarly simple. With composition, focus, and exposure set, all I had to do was watch the clouds and click the shutter, my heart filled with gladness….


A Sony 12-24 Gallery

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Permanent Change

Gary Hart Photography: Gray and White, El Capitan Through the Clouds, Yosemite

Gray and White, El Capitan Through the Clouds, Yosemite
Sony a7R III
Sony 12-24 f/4 G
1/40 second
F/8
ISO 800

Surrounded by towering granite walls that seem so permanent, Yosemite Valley is America’s poster-park for enduring beauty. But in the grand geological scheme, there’s nothing permanent about Yosemite. In my lifetime Yosemite has been visibly altered by drought, flood, and rockslides (not to mention human interference). Predating my arrival, Yosemite’s Anglo conquerors had a profound affect on the flora and fauna that prevailed in its prior centuries under Native care. And predating all human contact, glaciers performed their carve-and-polish magic on Yosemite’s granite.

But Yosemite’s history of change goes back much farther than that. Though it’s just a drop in the 4 1/2 billion-year bucket of Earth’s existence, let’s flip the calendar back to 100 million years before the glaciers scoured the area we call Yosemite, when layers of sediment deposited beneath a vast sea had been injected with magma that cooled to become granite. This subterranean granite was gradually uplifted by a slow-motion collision of tectonic plates that formed the mountains we call the Sierra Nevada. (Yes, I know this is a gross simplification of a very complex process.)

That’s a time-lapse I’d pay money to see, but lacking an actual 100-million-year time-lapse, I think Yosemite’s clouds make a wonderful metaphor for the park’s constant change. In fact, Yosemite storms are subject to the same the laws of nature that build and erode mountains. Each is the environment’s response to heat, moisture, pressure, and gravity—albeit on a different clock. Different in many ways, there’s also an interconnectedness to these natural processes: Just as the mountains have a profound affect on weather patterns, the weather is the prime force in the mountains’ erosion.

A month ago I got to watch the special choreography of Yosemite’s clouds and granite. Drawn by the promise of snow, I arrived as the storm built during daylight’s last couple of hours. Continuing to build under the cover of darkness, the storm was in full force by the morning’s first light. I woke to find snow covering every exposed surface, while overhead the mesmerizing dance of form and flow played out atop unseen air currents.

My first stop that morning was El Capitan Meadow. In summer, gawkers tailgate here to watch climbers monkey their way to the top of El Capitan. On this frigid morning El Capitan’s summit was a memory beneath a gray shroud, so I turned my camera to earthbound subjects within the small radius of my vision. In intense storms like this, ephemeral glimpses of Yosemite’s icons are a coveted reward that keeps experienced Yosemite photographers glancing skyward. Ever the optimist, despite a seemingly impenetrable low ceiling, I directed frequent glances in El Capitan’s direction as I worked.

The first suggestion of El Cap’s outline above the trees looked more like the faintest hint of a shadow in the clouds. I recognized what could be about to happen and quickly made my way to a better vantage point, watching until the shadow darkened and vague granitic detail appeared. Anticipating further clearing, I worked fast to beat the monolith’s inevitable reabsorption, switching lenses and framing a wide shot. To minimize tree-tilting perspective distortion, I raced across the road to increase my distance from the forest, raising my vantage point by scaling a snow mound piled atop a low fence by snowplows. With a breeze blowing the trees, I’d been shooting all morning at ISO 800, and the morning’s flat and constant light meant was no need to adjust my exposure. When the clouds parted just enough to frame El Capitan’s nose, I focused on the nearby trees and clicked several frames before the hole snapped shut.

An image like this is as much an opportunity to capture Yosemite’s snowy splendor as it is a revelation of something special about El Capitan. And that morning, my only thoughts about the clouds were wishes they’d disappear to show more granite. But as I started working on this image at home, I couldn’t help think about how clouds often provide the change Yosemite photographers seek in this (seemingly) unchanging place. That got me thinking about the nearby scar from last August’s tragic rockslide. On a clear day from the right vantage point, the scar is clearly visible on El Capitan’s east flank. another reminder that the only thing in Yosemite that’s permanent is change.


Yosemite’s Clouds

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Snow Job

Gary Hart Photography: Winter Reflection, Bridalveil Fall and the Merced River, Yosemite

Winter Reflection, Bridalveil Fall and the Merced River, Yosemite
Sony a7R III
Sony 16-35 f/2.8 GM
1/4 second
F/14
ISO 50

I’m afraid that making a living as a photographer sometimes means exchanging time to take pictures for time to make money. On the other hand, my schedule is mine alone, which means when there’s something I really, really want to photograph, such as a moonrise or fresh snow in Yosemite, I can usually arrange my schedule to make it happen. The moon shoots I can plan a year or more in advance, but snow requires a little more vigilance and flexibility.

Early this month, with hints of snow coming to Yosemite Valley, I started clearing space in my schedule. At 4000 feet, Yosemite Valley is often right on the snow-line, so a swing of just a couple hundred feet in either direction can mean the difference between snow and soggy. After watching the weather reports vacillate between snow and rain all week (and adjusting plans more than once), my buddy Mark and I took a chance and made the drive to Yosemite, visions of snowflakes dancing in our heads.

Waiting at the traffic-light-controlled, one-lane detour around the Ferguson Slide on Highway 140, I watched dozens of westbound headlights file past the four or five eastbound taillights idling at the light in front of us. With a storm imminent, it occurred to me that we were participating in a kind of changing of the guard, where the evacuating tourists are replaced by a much smaller contingent of what could only be photographers.

We arrived in Yosemite Valley at about the same time as the rain, circled the valley, secured a cheap room at Yosemite Valley Lodge (in Yosemite, any night with plumbing and solid walls for $150 is in fact a steal), and went to dinner. When the rain continued through dinner and all the way until bedtime, I began to fear the weather report had vacillated once more in the wrong direction.

Peeking out the window at around 4:00 a.m. and seeing more rain, I grudgingly turned off the alarm I’d optimistically set for 6:00 a.m. and went back to sleep. The next thing I knew, Mark was waking me at 6:10 to report six inches of fresh snow, and it was still falling. By 6:15 we were bundled and searching for my car in a parking lot filled with identical white lumps.

The rest of the morning was a blur as Mark and I darted from pristine location to pristine location, marveling at how a few hours of snow can completely transform  months of accumulated grime and a thirsty forest dotted with dead and dying trees. For those few hours, Yosemite was new again.

At our first stop, El Capitan Meadow, we photographed El Capitan and Cathedral rocks battling the clouds for dominance. Down the road at Valley View, the snow continued falling but the granite was winning and I soon found myself admiring the reflection of Cathedral Rocks and Bridalveil Fall just upriver from the parking area.

Normally the thin branches overhanging this vantage point are a distraction to avoid, but glazed with snow, they had the potential to make a perfect frame. The reflection was the easy part, but somehow I had to figure out how to feature it and the branches without the branches obliterating the rest of the scene.

To separate Bridalveil Fall and Cathedral Rocks from the glazed branches, I splayed my tripod’s legs and dropped it to the ground, then scooted up to the river’s edge. That still left a few branches dangling too low, so I pushed my camera out even farther by extending one tripod leg into the river. I was aided immensely by the articulating screen of my Sony a7RIII—while I still needed to sit in the snow to get low enough to compose and control my camera, I very much appreciated the ability to sit and look down at my LCD rather than sprawl on my stomach in the snow to get my eye to the viewfinder.

When photographing a scene that includes a reflection and nearby objects, it’s important to remember that the focus point of a reflection is the focus point of the reflective subject, not the reflective surface. (I’ll pause here for a few seconds to let you process this because it’s important.) In this case I was at 16mm; at f/11 that gave me a hyperfocal distance of less than four feet; with the branches about five feet away, front-to-back sharpness wouldn’t be a problem, even focused at infinity. Nevertheless, I chose f/14 for this shot, not for more depth of field, but to (along with ISO 50) stretch my shutter speed enough to smooth a few small ripples in the reflection.

Excitement about a scene can overwhelm good sense—we see something that moves us, and quickly point the camera and click with more enthusiasm than thought. While this approach may indeed record memories and impress friends, it almost certainly denies the scene the attention it deserves. I was indeed very excited about this scene, but between the depth of field, reflection, overhanging branches, moving water, dominant background subjects, not to mention the awkwardness of my position, I had many moving parts to consider.

Rather than attempt perfection on the first click, I addressed the obvious stuff (covered above) with a “rough draft” click. Draft image in hand, I popped my camera off the tripod, stood (ahhhhh), and evaluated my result. I immediately saw two things to address: first, I wanted Cathedral Rocks better framed by the branches; second, I wanted the mid-river, snow-capped rocks away from the right edge of my frame.

I returned my camera to live-view, dropped to ground-level, and replaced the camera on my tripod. Because I hadn’t touched the tripod, the scene on my live-view LCD was the very scene I’d just reviewed—making my prescribed adjustments was a simple matter of panning right a couple of inches and pushing the tripod a little farther into the river. Click.

I love my job.

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Yosemite Winter

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A Winter Morning in Yosemite

Gary Hart Photography: Winter Reflection, El Capitan, Yosemite

Winter Reflection, El Capitan, Yosemite
Canon EOS-1Ds Mark III
Canon 17-40
1/4 second
F/16
ISO 200

Missing snow so far this winter, I’m going through some of my old snow images and came across this one from a few years ago. I’d traveled to Yosemite with the promise of snow in the forecast, but the night before the trip’s final day I went to sleep to the steady hum of rain. The next morning dawned damp and gray—and gloriously silent. Outside a thin veneer of fresh snow dusted the trees, and without even considering breakfast I headed to Tunnel View to survey the valley and plan my morning. By the time I arrived a patch of sunlight had burned a hole in the clouds above Cathedral Rocks and hints blue sky mingled with the clouds behind me. I knew the show there would soon be spectacular, but I’ve photographed many clearing storms from Tunnel View and wanted something different.

Without leaving my car I headed back down into the valley, stopping first at El Capitan Bridge, arriving just before the clouds atop El Capitan started lifting. I photographed there for about 15 minutes, long enough to see El Capitan’s nose go from obscure shadow to distinct outline to fully exposed granite. Before the clouds parted completely, I packed up and made a beeline for nearby Cathedral Beach. In the short time it took to drive a half mile most of El Capitan had emerged from the clouds and I rushed to grab my gear. The road to the beach was closed so I set out on foot, running most of the quarter mile to the river.

I found two other photographers at the west end of the beach and rather than compete with them for real estate, I trudged through the brush and fresh snow to an open space just downstream. There I was able to set up in solitude and move around at will. I was quite pleased to find a snow covered snag protruding from the river, adding a little depth to the foreground.

The beauty of photographing a Yosemite clearing storm is that no matter where you are, something spectacular is happening. Often in these situations I move between locations much more quickly than normal, but this morning I took my time and just enjoyed the show.

Wringing out as many compositions as possible, I started wide with both vertical and horizontal compositions that included El Capitan and the reflection. Next I went a little tighter, capturing just El Capitan, or just the reflection, or some of both. Finally I switched to a telephoto and started picking out individual elements: the swirling clouds and brilliant highlights on El Capitan’s vertical edge, the snow covered snag in the river, and so on.

Technical stuff

A couple of related technical issues raised by this image: First, the focus point of a reflection; and second, where to focus when elements are spread from near to far throughout the frame. It’s counterintuitive to many that a reflection’s focus point is the focus point of the reflective subject, not the reflective surface. In other words, since El Capitan is at infinity, its reflection is in focus at infinity, and not when focused on the snag. If you don’t believe me, try it yourself.

Given that knowledge, and the fact that I generally want whatever’s in my foreground to be in focus (even if it means the background is slightly soft), I had to find a compromise focus point to ensure that both the reflection and the snag were in focus. With an extremely wide focal length and small aperture I was confident I could get the entire scene acceptably sharp if I focused carefully.

There are different approaches to maximizing focus range, such as relatively accurate but awkward hyperfocal charts, and rule-of-thumb guidelines like focusing a third of the way into the frame. Both have merit, and many excellent photographers employ them, but I prefer a more seat-of-the-pants approach that relies on my own experience and understanding of focus range. I generally find the closest subject I want in focus—in this case the snag—and then focus on something a little behind it.

Here I estimated the distance of the snag, found something behind me that I thought was a little farther away, and focused there. At f/16 that gave me a pretty large margin for error and I was confident the image was sharp throughout. Is this an approach I’d recommend for others? Perhaps, though it takes trial and error to perfect. I encourage you to familiarize yourself with hyperfocal distances–you don’t need to memorize them, but a basic understanding of the relationship between f-stops, focal lengths, and focus distance is invaluable for decisions like this.

Here’s an article from my Photo Tips section that might help: Depth of Field.

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Winter in Yosemite

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How a polarizer works

Gary Hart Photography: Autumn Reflection, North Lake, Eastern Sierra

Autumn Reflection, North Lake, Eastern Sierra (2010)
Canon EOS-1Ds Mark III
Canon 17-40L
1/5 second
F/16
ISO 200

Some people couldn’t care less how a polarizer works—they’re satisfied knowing what a polarizer does, and how to make it happen. But if you’re like me, you also need to understand why things behave the way they do.

Put simply…

A polarizer eliminates reflections. On the surface that not might seem so desirable for someone who likes photographing reflections as much as I do, but reflections are a much bigger part of our visual experience than most people know. Virtually every object reflects at least a little, and many things reflect a lot more than we’re aware. Worse still, these reflections often hide the very surface features and color we most love to photograph.

When reflections hide an object’s underlying beauty, a polarizer can restore some of that beauty. I use a polarizer when I want to capture the submerged rocks or sand hidden by the reflection atop a river or lake, the rich color overwhelmed by glare reflecting from foliage, or the sky’s deep blue washed out by light scattered by atmospheric molecules.

Put a little less simply…

In reality, reflections are merely collateral damage to your polarizer. What a polarizer really does is eliminate light that’s already been polarized. To understand what’s really going on with a polarizer, read on….

Essential terminology

  • Oscillation is motion relative to a fixed point. For example, when you snap a whip, the whip “oscillates” along its length. Without external interference (e.g., friction from the atmosphere or other objects), motion in one direction along the whip will have an identical motion in the opposite direction (e.g., up=down, left right, and so on), and that motion will move forward along the whip.
  • wave is oscillation along or through a medium (such as air, water, or space). The bulge that moves up and down (oscillates) along a cracked whip is a wave. For the liberal arts folks, (in this context) wave is a noun, oscillate is a verb. A wave is measured by its wavelength and frequency—the higher the “frequency,” the shorter the “wavelength.”
  • Frequency is the number of times a wave peak passes a discrete point in a given unit of time (usually one second: “per second”).
  • Wavelength is the distance from one wave peak to the next at any instant frozen in time.
  • A transverse wave oscillates perpendicular (90°) to its direction of motion. To imagine the motion of a transverse wave, picture an ocean wave, which oscillates up and down as it advances through the water. Now think about a bottle floating in the open ocean—bobbing up and down with each wave, it’s up/down motion is perpendicular to the wave’s forward motion, but when that wave has passed, the bottle is in the same place it was before the wave arrived. (Waves don’t move bobbing bottles across the ocean, currents do.)
  • Visible light is electromagnetic radiation that reaches our eyes as a transverse wave somewhere in the wavelength range the human eye can register, about 380 to 740 nanometers (really small).
  • Sunlight (or more accurately, solar energy) reaches earth as a transverse wave with a very broad and continuous spectrum of wavelengths that include, among others, the visible spectrum (lucky for photographers), infrared (lucky for everyone), and ultraviolet (lucky for sunscreen vendors). The oscillation of solar energy’s transverse wave is infinitely more complicated than an ocean wave because light oscillates in an infinite number of directions perpendicular to its direction of motion. Huh? Think about the blades of a propeller—each is perpendicular to the shaft upon which the propeller rotates, so in theory you can have an infinite number of propeller blades pointing in an infinite number of directions, each perpendicular to the shaft. So a light wave oscillates not just up/down, but also left/right, and every other (perpendicular) angle in between.

Polarization

While an unpolarized light wave oscillates on every plane perpendicular to the wave’s motion, polarized light only oscillates on one perpendicular plane (up/down or left/right or 45°/225° and so on).

Polarization can be induced many ways, but photographers are most interested in light that has already been polarized by reflection from a nonmetallic surface (such as water or foliage), or light that has been scattered by molecules in our atmosphere. Light scattered by a reflective surface is polarized parallel to the reflective surface; light scattered by molecules in the atmosphere is polarized perpendicular to the direction of the light.

Polarization can also be induced artificially with a polarizing filter (“polarizer”), a filter coated with a material whose molecular structure allows most light to pass, but blocks light waves oscillating in a specific direction. When unpolarized light (most of the light that illuminates our lives) passes through a polarizer, the light that enters the lens to which it’s attached has been stripped of the waves oscillating in a certain direction and we (through the viewfinder) see a uniform darkening of the entire scene (usually one to two stops).

But that uniform darkening is not usually what we use a polarizer for. (I say usually because sometimes we use a polarizer to reduce light and stretch the shutter speed in lieu of a neutral density filter.) Photographers are most interested in their polarizers’ ability to eliminate reflective glare and darken the sky, which occurs when their polarizer’s rotating glass element matches the oscillation direction of light that has already been polarized by reflection or scattering, cancelling that light. By watching the scene as we rotate the polarizing element on the filter, photographers know that we’ve achieved maximum polarization (reflection reduction) when we rotate the polarizer until maximum darkening is achieved—voila!

The exception that proves the rule

Most photographers know that a polarizer has its greatest effect on the sky when it’s at right angles (90°) to the sun, and least effective when pointed directly into or away from the sun (0º or 180°). We also know that a rainbow, which is always centered on the “anti-solar point” (a line drawn from the sun through the back of your head and out between your eyes points to the anti-solar point) exactly 180° from the sun, can be erased by a polarizer. But how can it be that a polarizer is most effective at 90° to the sun, and a rainbow is 180° from the sun? To test your understanding of polarization, try to reason out why a rainbow is eliminated by a polarizer.

Did you figure it out? I won’t keep you in suspense: light entering a raindrop is split into its component colors by refraction; that light is reflected off the back of the raindrop and back to your eyes (there’s a little more bouncing around going on inside the raindrop, but this is the end result). Because a rainbow is reflected light, it’s polarized, which means that it can be eliminated by a properly oriented polarizer.

About this image

Long before achieving international fame as the background scene for Apple OS X High Sierra, North Lake at the top of Bishop Canyon in the Eastern Sierra has been beloved by photographers. Each autumn this little gem of a lake teams with photographers longing for even one of the following conditions: peak gold and red in the aspen, a glassy reflection, or a dusting of snow.

I visit North Lake multiple times each autumn, sometimes with my workshop groups, sometimes by myself. I’ve found pretty much every possible combination of conditions: snow/no-snow; early, peak, or late fall color; and a lake surface ranging from mirror smooth to churning whitecaps.

One sunrise early October of 2010 I hit the North Lake trifecta. Crossing my freezing fingers that the reflection would hold until I was ready, I lowered my tripod on the rocky shore and framed the aspen-draped peak and its vivid reflection. I used a couple of protruding rocks to anchor my foreground, slowly dialed my polarizer until the entire lake surface became a reflection, and clicked. But rather than settle for that shot, I reoriented my polarizer until the reflection virtually disappeared and a world of submerged granite rocks appeared. I clicked another frame and stood back to study the image on my LCD.

As much as I liked the rocky lakebed version, I knew there was no way I could pass on the best reflection I’d ever seen at North Lake. So I returned my eye to my viewfinder and very slowly dialed the polarizer again, watching the reflection reappear across the lake and advance toward me until the entire mountain unfolded in reverse atop the lake. Stopping just at that midway polarization point, I had the best of both worlds: my pristine reflection and an assortment of submerge rocks.

I Use Breakthrough Filters


Dialing In My Polarizer

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