The Exposure Triangle

 We can’t really get down to the business of the field—the 'traverse' through the sagebrush, the waiting for the 'light to carve out the texture' of a canyon wall—without first talking about the basics, can we? It’s like trying to understand the 'geology of a region' without knowing your 'igneous' from your 'sedimentary'. You need the fundamentals, the quiet, solid framework upon which all the 'really interesting' work is built.

The Stillness of Light: An Essential Overview

In the end, all that separates a photographer from the light itself is a small mechanical box, and our ability to control what that box does. Things have changed, of course. Film is mostly a beautiful memory for many, replaced by the 'digital sensor', that sensitive electronic eye. But the underlying process? It’s as constant as the current in a river. We’re still just controlling 'how much light' reaches the medium.

I first learned this process by running those strips of film through my camera—a discipline that taught me the 'weight' of every decision. That essential control is known in the trade as the 'Exposure Triangle'. It's the central mechanism, the 'governor' of illumination.

Now, before we plunge into the specifics of my own workflow—the 'logistical challenges' and the 'quartermaster's ledger' entries that fill my notebooks—we need to pause and make sure we’re all operating with the same baseline understanding. This little 'side trip into the Exposure Triangle isn't a distraction; it's the map key. It’s the gentle reminder that what we do with the camera's settings—what seem like mere numbers and clicks—are really just our means of telling the 'landscape how to present itself'.

This quick overview should serve as a friendly, steady reference point. It’s here to make my future field discussions easier to follow, to let you know exactly 'why' I've chosen a certain setting when I'm discussing a particular image. And for me? Well, organizing information to teach others always 'refines my own understanding' a good review of the process is always a 'quiet goodness.

Let’s step into the light together, shall we? 📸

What aspect of the Exposure Triangle—'aperture', 'shutter speed', or 'ISO'—would you like to start with?

Wrangling Photons: A Field Guide to the Exposure Triangle

It’s a familiar feeling for any photographer. You’re scrolling through a dozen shots of the same waterfall, and most are… fine. The first is a mess—too dark, too bright, clearly incorrect. The second is technically okay; the highlights are where they should be, the shadows behave themselves, and by all accounts, it is a correctly exposed image. But the third one… the third one sings.

This third image, what we’ll call the "creatively correct" one, has something more. It possesses a greater sharpness that carries your eye throughout the entire frame, and the motion of passing vehicles has a blur that is not just blurry, but pleasingly so. These three images demonstrate the gulf between a machine’s correct decision and an artist’s intentional one. The goal isn't just to capture a scene, but to make deliberate choices that elevate it. This guide is about demystifying the fundamental language of photography so that you can gain mastery over your camera and start making those creatively correct choices yourself.

The Language of Light: Understanding Exposure

To understand photography is to understand its most basic component: light. The central concept that governs this is called "exposure," and learning it is the first step in learning to "speak camera." In fact, a finished photograph itself is often called an "exposure."

In a photographic context, Exposure is simply the amount of light that passes through your lens and your camera's shutter, ultimately registering on a photosensitive medium—be it a digital sensor or a frame of film.

Three core mechanisms, our main characters in this photographic story, control this flow of light: Aperture, Shutter Speed, and ISO. These three factors are at play in every single image you take, whether you are aware of them or not. To move from taking correct pictures to creating creatively correct ones, you need to get to know this trio intimately.

Meet the Trio: The Three Levers of Light

Each member of our exposure trio has a primary job in controlling the amount of light that enters the camera. But just as importantly, each one comes with a unique "side effect"—a secondary characteristic that you, the photographer, can use to inject creative flair into your images. Let's meet them one by one.

 Aperture: The Pupil of the Lens

At its heart, the concept of Aperture is simple: it’s the size of your lens's entrance pupil. Just like the pupil in your eye, the more it’s dilated, the more light it lets in.

This is where things get a little weird. Aperture is measured in values called F-stops, with numbers like F/1.4, F/4, or F/22. Here’s the one quirky rule you’ll need to remember: the smaller the F-number, the bigger the opening. It feels backwards, but once it clicks, you'll never forget it.

For the technically curious, an F-stop is a ratio: the focal length of your lens divided by the stop in use. As one of my mentors wisely notes, this is "not necessary information by any means," but it helps explain why a smaller number means a bigger hole.

Aperture's Creative Side Effect: Depth of Field

This is where you, the photographer, get to play god with focus. Aperture's most powerful artistic tool is its control over Depth of Field (DOF), which is the range of things that will be in focus in your image.

• Shallow Depth of Field: A large aperture (like F/2.8) creates a very shallow plane of focus. This is how portrait photographers get that razor-thin focus on their subject against a "milky out of focus background." It isolates the subject, making them pop.

• Great Depth of Field: A small aperture (like F/11 or F/22) keeps nearly everything in the frame sharp, from the flowers at your feet to the mountains on the horizon. This is the go-to choice for landscape photographers who want clarity throughout the scene.

Shutter Speed: The Blink of an Eye

Shutter Speed is exactly what it sounds like: the length of time the camera's shutter remains open, allowing light to hit the sensor. It’s measured in seconds or, more commonly, fractions of a second (e.g., 1/250s or 1/30s).

Shutter Speed's Creative Side Effect: Motion Capture

Shutter speed dictates how motion is recorded in your photograph, giving you the power to either freeze a moment in time or embrace the blur of movement.

• Freezing Motion: A fast shutter speed, like 1/250th of a second, is quick enough to capture a moment with crystalline clarity. In a photo of a waterfall, it would make the water appear frozen in time.

• Blurring Motion: A slow shutter speed, like 1/30th of a second, allows moving objects to streak across the frame. That same waterfall would now look soft and "streaky." Very long shutter speeds are how photographers capture the iconic light trails from vehicle headlights at night.

ISO: The Sensitivity Dial

ISO refers to the sensitivity of the film or digital sensor to light. The concept comes from the film world, where a film stock's sensitivity was part of its name—like Colorplus 200 or Portra 800. The higher the number, the more sensitive the film is to light. Digital cameras have the incredible advantage of being able to change their ISO at any time. On a digital camera, a higher ISO is essentially an electrical amplification of the light signal, also known as "gain."

ISO's Trade-off: Grain and Digital Noise

This sensitivity comes at a cost. Increasing the ISO introduces more grain (on film) or digital noise (on digital cameras). Now, film grain can sometimes be a pleasing stylistic choice, adding texture and mood. Digital noise, on the other hand, is "not particularly pleasing." For the cleanest, highest-quality image possible, the ideal is to always shoot at your camera's Base ISO, which is usually the lowest number available (like 100 or 125).

Now that we've met our trio in theory, let's head to a waterfall and see them in action. This is where the real learning begins.

The Balancing Act: The Exposure Triangle in Action

Aperture, Shutter Speed, and ISO are so interconnected that photographers refer to them as the Exposure Triangle. The name is a perfect metaphor: if you change one of the three points, you must adjust one or both of the others to compensate if you want to maintain the same level of brightness in your image.

Let’s walk through a real-world example to see this balancing act in the field.

The Goal: A Correct (But Uninspired) Shot

Imagine we’ve found a beautiful landscape and, knowing nothing, we put our camera on Auto. We take a picture, and it looks decent. The camera gives us settings of F/4, 1/250s, and ISO 125. The exposure is correct, but because this is a landscape, our creative goal is to get more of the scene in focus—we want a greater depth of field.

The First Move: Chasing Sharpness

To achieve this, we switch to Manual mode and change the Aperture from a middling F/4 to a much smaller F/11. We take the shot. The result? Something is "terribly wrong." The image is now far too dark. We successfully increased our depth of field, but in doing so, we "took away a bunch of light."

The Language of Balance

How much light did we take away? Photographers measure light in Stops. One stop is a doubling or halving of the amount of light. The jump from F/4 to F/11 is a decrease of three stops of light. We need to add those three stops back.

The First Trade-Off: Compensating with ISO

Our first thought might be to increase the ISO. To make up for three stops of lost light, we'd need to increase the ISO from 125 to 200 (one stop), then to 400 (two stops), and finally to 800 (three stops). We take the photo, and the exposure is correct again! But when we look closely, the image shot at ISO 800 has significantly more grain than our clean original. This isn’t the quality we’re after.

The Final Solution: Compensating with Shutter Speed

Unhappy with the noise, we decide to return to our clean Base ISO of 125. This leaves only one lever to pull: Shutter Speed. We need to lengthen our shutter speed by three stops to let in more light. Starting from 1/250th of a second:

• One stop slower is 1/125s.

• Two stops slower is 1/60s.

• Three stops slower is 1/30s.

We set the shutter to 1/30th of a second and take the picture. Success! The image is now correctly exposed, sharp from front to back (thanks to our F/11 aperture), and clean (thanks to our Base ISO). But it has a new quality: the water in the scene, which was frozen at 1/250s, now has a soft, streaky motion blur.

Notice what we did here: we started with a correct auto-exposure and, through a series of intentional trade-offs, arrived at this creatively correct image—one that is not only well-exposed but also sharp and dynamic in a way the camera could never have achieved on its own.

This step-by-step process wasn't just a technical exercise; it was a creative one, which brings us to the heart of intentional photography.

From Technical to Intentional: The Art of the "Creatively Correct"

Mastering the exposure triangle isn’t about memorizing numbers; it’s about learning to make deliberate, intentional choices. It’s about looking at a scene and deciding which creative side effect—depth of field, motion capture, or image cleanliness—is most important for the story you want to tell.

Before you press the shutter, ask yourself these questions:

• How much Depth of Field do I want in this image? This is an Aperture question. Do you want to isolate a subject or capture a sweeping, sharp landscape?

• Is there Motion I need to be aware of, and how do I want it to register? This is a Shutter Speed question. Do you want to freeze the action or show its flow?

• What is the cleanest ISO I can use? This is an ISO question. Can you shoot at your Base ISO, or does the situation force you to accept some noise?

A camera on auto mode is capable of making a correct decision. It can balance the triangle to get a decent exposure. But it is not smart enough to make the best decision. It does not have creative problem-solving abilities. You do.

Your Training Wheels for Manual Mode

Jumping straight into full Manual mode can feel intimidating. Luckily, as we find a new scene to practice on, we can try out Priority Modes. Think of them like training wheels on a bicycle. They exist in the middle of the spectrum, between full automatic and full manual, providing stability by managing one variable for you so you can focus on learning to balance the other.

• Aperture Priority (A or Av): In this mode, you choose the aperture you want, giving you direct control over depth of field. The camera will then automatically select the shutter speed needed for a correct exposure. This is perfect for portraits or landscapes where depth of field is your primary creative concern.

• Shutter Priority (S or Tv): Here, you choose the shutter speed, giving you control over motion capture. The camera then selects the appropriate aperture. This is ideal for sports or action photography where freezing or blurring motion is your main goal.

These modes are fantastic learning tools. By setting one variable yourself and observing how the camera compensates with the other, you begin to build an intuitive understanding of how the triangle works. As the source of this wisdom once said, "It's just like riding a bike with the training wheels on for a little bit. And it's fun because you get the same results with less work."

Finding Your Style

The journey from a technically correct snapshot to an intentional, creatively correct photograph is one of the most rewarding in photography. It's a path that begins with understanding these fundamentals. Aperture, Shutter Speed, and ISO are not just settings; they are the levers of artistic expression, the "foundations of photography." By learning to balance their technical demands with your own vision, you unlock a new level of control and creativity.

"Combine technical understanding with creativity and you will never have to worry about finding your style. It will find you."

Thanks for stopping by and having a read.

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved

Recon

 

The Preliminary Traverse: A Geographer's Notebook

The first look at a place is not an act of creation; it is reconnaissance with intent. It is less a formal survey than a quiet, almost diffident introduction—a walkabout undertaken to absorb the land’s temperament. Before the heavy, deliberate machinery of a camera is unshouldered, before a tripod is leveled and locked, the geographer of light must conduct a preliminary traverse. The purpose of this initial, unhurried journey is not to make a photograph. It is to have a conversation with the place itself.

This traverse is often an incidental affair, a day trip perhaps with the family in tow. The pressure to produce is absent, leaving the professional eye free to work in the background of a leisurely excursion. The final image is sown here, in this absorption. One might take a few field notes with a cell phone camera, but these snapshots are not for the portfolio. They are visual data—a means to study the transient architecture of light. A noon sun might flatten a river valley, turning it into a stark, unreadable map, while the late afternoon light carves texture into the hillside, revealing contours previously invisible. The cell phone, then, is merely an unassuming tool for sketching out the possibilities that a more deliberate return trip might capture. From the physical act of walking the land, the work shifts to the intellectual task of recording these fleeting observations.

Every site possesses its own passion: a unique combination of the visual, the aromas, and the sounds. The scent of damp earth, the particularity of the wind’s voice through the sagebrush—these are data points. Captured audio, when combined with the simple visuals, helps define the place. Returning home and listening to those audio notes—the subtle counterpoint to the digital imagery—enhances the planning, refining the initial reconnaissance into a project with defined goals, design, and execution. Each subsequent visit is a further refinement; every hour provides new moments for consideration. And the presence of others, their awareness of the photographer's watchfulness, can surprisingly enhance the seeing, their fresh perspective helping to define the conversation with the landscape.

The Cartographer's Notebook: A Mapping of Potential

The most essential instrument for this kind of work is not a lens, but a notebook. It is here that the ephemeral—a promising slant of light, a logistical challenge—is made permanent. This cartographer’s ledger is not a mere account book of facts; it is the primary tool for mapping the creative and practical terrain of a future expedition. It transforms a day's pleasant ramble into a workable strategy.

One begins by inscribing what is seen: a lone piñon pine on a western ridge, a derelict barn. Then, one begins to test how these might be rendered. The notebook might read: “Primary subject: lone piñon pine. Afternoon light catches the trunk, turning bark deep ochre. Try a low-angle shot from the southeast to frame it against the empty sky; shadow falls long towards the wash.” This is the moment to document how a subject's character shifts with a change in perspective. Latitude, longitude, and altitude are logged not merely for orientation, but to predict the precise movement of sun and moon, transforming a hopeful guess about light into a precise appointment. Altitude, furthermore, allows for a reasonable guess at temperatures after dark or before dawn—a crucial bit of data for an alpine start.

This entire practice is rooted in a discipline of complete situational awareness. The directive to "keep your head on a swivel" is a professional's call to resist the tunnel vision that settles upon a single subject. The alert eye scans for other elements—an unexpected detail, a surprising juxtaposition—just beyond the immediate point of focus. These discoveries, too, must be inscribed in the notebook, logged as opportunities to be explored upon return.

Alongside creative possibilities, the notebook must hold the mundane but critical data that makes a professional endeavor possible. Logistical facts are the framework for the creative work: travel vitals—the date, time, and vehicle mileage—are recorded; the time spent on site is noted. If the "site is appropriate for time-lapse, bring a chair.” A simple note about bug spray can save a future trip. This data is critical for planning the return and, on a financial level, for substantiating expenses. These notes, written at the site, are a conversation with the photographer of the future—a sage voice in a comfortable living room speaking to the one in the field: “This is what I will need,” they say. “This is what I want to bring home.”

The Quartermaster's Ledger: Sustenance and Situation

A successful shoot is built upon a foundation of non-photographic planning. Securing logistical support—the necessities of food, fuel, and shelter—is as fundamental to the outcome as choosing the right lens. Like any expedition leader, the photographer knows that a failure in the supply lines—a missed meal, an empty gas tank—can compromise the entire enterprise. The quartermaster’s ledger, a dedicated section of the notebook, ensures that the artist is free to focus on the art.

This practical mapping involves identifying local resources. Where can one get gas? A reliable place to eat? If the project requires an overnight, where can one sleep? For those who camp, a suitable spot must be found in advance. This forethought is about efficiency and readiness. The rhythms of landscape photography often conflict with the quiet hours of a campground—arriving late after a sunset shoot or leaving before dawn for a sunrise. An ethical approach is to select a campsite near the entrance or to park and walk in quietly.

In the modern context, one final logistical checkpoint is crucial: confirming cell phone connection. It is not a convenience, but a vital check for communication and safety, a lifeline in case of an emergency. Including a GMRS or UHF/VHF radio will increase your safety in the backcountry; learning the Wilderness Protocol and having a communication plan is non-negotiable. The quartermaster's planning can even involve personal habits. The photographer with a morning “visit of the necessaries” cycle might decide not to eat the day before a sunrise shoot. A disciplined personal practice, such as a 48-hour fluid-only rule, is easily learned. Trying to find a pit toilet in a National Park is not what one wants to be doing when on-site in sub-freezing temperatures. There is plenty of time to eat a fine breakfast at a restaurant after the shoot, an opportunity that also allows for the finalization of notes and the planning for post-production. Then, home for a file backup, and a nap.

The Calculus of Return: A Final Reckoning

The final stage of planning is a synthesis of all prior reconnaissance—a moment of quiet reckoning. Before committing the significant time and resources of an actual photoshoot, one must consult the cartographer’s notebook, holding the initial field sketches and logistical data against a series of frank questions. This assessment, a final calculus, determines the project’s fate.

The core question is: “Is this worth the time? Can I get an image here I like?” This query moves beyond technical feasibility to the heart of creative satisfaction. The results sought are for expressing the essence of what brought the photographer to this place; they are not to please others but to record what defines the artist's knowledge and emotions. The safety protocol is next: “Do I need to take backup or arrange safety checks?” A sober assessment of the risks ensures preparation aligns with the realities of the location. A plan for communication is made; accidents happen. The artistic approach is considered: “What style of shooting will I commit to?” This forces a commitment to a specific vision. Equipment considerations follow: “Does the location allow my full kit or do I need to consider carry weight?” Every piece of gear is chosen with purpose, informed by the careful geography of that first, quiet traverse.

What does the geographer of light see that others miss? The geographer informs the photographer. As with most aspects of the work, the training of a field geologist determines the approach to seeing, the workflow, the vision, and the art. The landscape is the book being read; it is always the instructor. I capture images, I learn more. I record moments.

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved

A Hard Rain’s A‐Gonna Fall

I've stepped in the middle of seven sad forests,
I've been out in front of a dozen dead oceans,
I've been ten thousand miles in the mouth of a graveyard,
And it's a hard, and it's a hard, it's a hard, and it's a hard,
And it's a hard rain's a-gonna fall.

                   -- Bob Dylan

The silence has a grain to it, a texture suggesting it is not an absence of sound but a thing in itself, accumulated over time. My camera, an instrument of the present moment, is fixed to its tripod, its lens directed toward a wall of Entrada Sandstone. In the late-afternoon light, the rock seems to absorb the sun and hold it internally, a slow, deep orange reminiscent of cooling iron. To be here, on the Colorado Plateau, is to be in a place that has winnowed its vocabulary down to a single, resonant word: aridity. The air has a desiccated edge. The landscape is an open book of geomorphology—fin, arch, hoodoo, canyon—all of it incised from what are known collectively, and with a certain plainspoken poetry, as the red beds. These are the lithified archives of an erg, a sea of sand that blew across this part of the world for millennia we can only guess at. Every visible plane and exfoliating surface is a narrative of stone and sun, of a world shaped by a thirst so profound it has become structural.

This, however, is the story on the dust jacket. The central paradox of this landscape—the geological non sequitur that brings me here—is that this paragon of dryness is also the tombstone of a drowned world. The evidence is here, but it is cryptic, written between the lines. Spliced into the thick, ruddy volumes of aeolian sandstone—the unmistakable signature of wind-deposition—are discordant passages. Thin, dark seams of gray shale, the compressed and settled muds of deep, anoxic lakes, have no business in a desert narrative. Even more incongruous: coal. Coal is the geologic ghost of a swamp, the carbon memory of a forest so fecund and waterlogged that its dead were buried faster than they could decay. Finding a coal seam in Triassic desert rock is like finding a receipt from a shipyard in a pharaoh's tomb. It points to a chapter of earth history that has been almost completely effaced, the story of a planet subjected to a rainstorm that lasted nearly two million years.

How, then, does this knowledge re-calibrate the eye? How does one frame a photograph of stone and sun while knowing that it is equally a monument to a global deluge, a climatic convulsion that reset the terms of life on Earth? A camera captures surfaces. The story is in the stratigraphy. To see the layers, you must first imagine the world as it was before the sky broke.

To comprehend the scale of the demolition, you must first walk the halls of the edifice that was destroyed. The Carnian Pluvial Episode was not a genesis event; it was a foreclosure. It brought down a planetary regime that had persisted for forty million years, an ecosystem of such apparent stability it might have seemed permanent. Its termination was not a gradual shift but a violent erasure.

Picture the planet 234 million years ago. The continents are welded into one supercontinent, Pangea, a single terrestrial mass stretching nearly from pole to pole. Its vast interior is a hyper-arid desert that would make the modern Sahara seem temperate—an expanse of rock and oxidized sand under a punishing sun. Life was a marginal enterprise, clinging to the coasts and the ephemeral river systems, while the continental heartland was left to the wind.

The dominant life forms, the undisputed proprietors of the planet, were a group of archosaurs called crurotarsans—the so-called "crocodile-line" reptiles. These were not the placid, semi-aquatic ambush hunters of today. They were a bestiary of terrestrial authority. There were giants like Sarcosuchus, a predator twenty-five feet long with a skull built for brute force, and things like Postosuchus, which stood high on its legs and moved like a reptilian grizzly bear. They were the lions and the wolves of the Triassic. They hunted a curious assortment of herbivores: the dicynodonts, mammal-like reptiles with tusks and beaks, whose fossils are so widespread they became a key piece of evidence for continental drift; and the rhynchosaurs, stout reptiles with shearing beaks designed for processing the tough, low-growing flora of a dry world. As for the dinosaurs, they were a minor guild. They were small, mostly bipedal, and lived in the margins—the Triassic equivalent of field mice, scurrying under the feet of the true rulers, their existence predicated on not being noticed.

This was the pre-lapsarian world: a planet of baked earth, governed by a forgotten dynasty of super-crocs, its climate a model of arid stability. It had no inkling that its lease was about to expire.

The agent of change came not from the heavens but from the mantle. The trigger for the two-million-year rain was a rupture in the planet’s crust, a deep wound that bled magma for half a million years. Geologists call it the Wrangellian Large Igneous Province, a flood basalt eruption that tore through thousands of square miles of what is now western North America. The lava was not the primary weapon. The gases were.

The mechanism was a two-act play of planetary violence. First came a cooling. The initial blasts injected immense quantities of sulfur dioxide into the stratosphere. The SO₂ reacted with atmospheric water to form a veil of sulfate aerosols, reflecting solar radiation back into space. The result was a brief, sharp “volcanic winter.” The rain that fell was acidic, poisoning soils and surface waters.

Then came the heat. The sulfur shield was transient, precipitating out of the atmosphere within years. The second gas, carbon dioxide, was not. The volume of CO₂ venting directly from the mantle was significant, but it was amplified by a secondary effect. As the magma punched upward, it intruded into and effectively cooked vast, deeply buried deposits of ancient coal and hydrocarbons, liberating their carbon. It was a planetary-scale fossil-fuel event, running in reverse. For five hundred thousand years, this volcanic province steadily pumped greenhouse gases into the air, wrapping the planet in a thermal blanket it could not shed.

The planet’s thermostat was broken. The oceans heated up, and as surface temperatures rose, evaporation rates skyrocketed. The atmosphere became saturated with water vapor—itself a potent greenhouse gas—creating a runaway feedback loop. The world was now a superheated, hyper-humid system. The atmospheric engine, overcharged and pressurized, had only one way to vent. It began to rain.

To move past the geological mechanics is to try to imagine the texture of life during the Carnian Pluvial Episode. It was not a steady drizzle but a mega-monsoon that pulsed across the globe for two million years—long, torrential wet seasons alternating with brutally hot, evaporative dry seasons. The great red deserts became mires. Rivers on an Amazonian scale would incise themselves into the bedrock, only to vanish when the cycle swung back to dry.

The air would have felt heavy, hot, and so saturated it would be like breathing steam. The world was a greenhouse with a fever, the heat radiating not just from a clouded-over sun but from the sodden ground itself. During the wet periods, every surface would have been slick with moisture, filmed with algae and cyanobacteria. The prevailing smell would have been of petrichor, rot, and fermenting vegetation.

The ground itself became unreliable. The stable, wind-scoured plains of Pangea were replaced by endless mudflats and braided, sediment-choked rivers. A dry wash could become a slurry flow of rock and water in minutes. Solid footing was a luxury. In this world, survival was not about finding food but about finding a patch of ground that would hold your weight. The new climate was not merely inclement; it was a specific kind of assassin, seemingly designed to dismantle the forty-million-year-old ecosystem.

Who survives a world like that?

The Carnian Pluvial Episode was a great filter. It did not kill randomly. It selected against the incumbents and for the marginalia. The ruling crurotarsans were exquisitely adapted to a dry, stable world. In the new regime of oscillating mud and baked earth, their strengths became liabilities.

Their very size was a disadvantage. The tonnage of a Postosuchus, so effective for intimidating rivals on firm ground, became a fatal burden in the muck of the wet seasons. Their specialized food web collapsed. The new, perpetually damp climate favored taller, more fibrous conifers over the low-lying plants that herbivores like the rhynchosaurs and dicynodonts depended on. As the prey base vanished, the apex predators starved. As ectotherms, the great reptiles relied on the sun to regulate their metabolism. In a world of perpetual cloud cover and chilling damp, they would have become sluggish, vulnerable, unable to effectively hunt.

When the last of the great crocodile-line archosaurs became mired in the mud, it left a power vacuum unprecedented in the history of life on land. The niche of apex predator had not so much been vacated as erased. And from the undergrowth stepped the dinosaurs. They did not triumph through direct competition. They triumphed because they were accidentally pre-adapted to the new, miserable conditions. They had three advantages. Their bipedal posture, common among early forms, kept their bodies higher off the treacherous ground. Evidence suggests they were endothermic, or nearly so—they carried their own internal furnaces, allowing them to remain active in the damp gloom. And their respiratory system, with its uniquely efficient, bird-like flow-through design, was a biological supercharger in a hot, humid, and likely oxygen-stressed atmosphere.

The rise of the dinosaurs was not a conquest. It was an accident of inheritance. A geological catastrophe had killed the old kings and ruined their kingdom. The dinosaurs were simply the only ones left who could tolerate the new world order.

I pack away the camera. The sun is gone, and the Entrada sandstone has cooled to a deep purple. The silence returns, but it is layered now. It is no longer the silence of an empty desert but the quiet that follows a storm of unimaginable duration. I came here to photograph a landscape. I found, instead, the depositional history of a world remade by fire and flood.

The red rocks are not just symbols of an ancient desert. They are the pages of a book, and the thin, dark lines of shale are not errata; they are the hinge of the plot. To photograph this place is to try to frame a story of collapse and contingency—the sheer, dumb luck that put the dinosaurs on a throne they would occupy for 150 million years, and in so doing, cleared a path that would eventually lead to us. Dominance, the rocks suggest, is an artifact of conditions. Strength is situational. The history of life is written not by the powerful, but by the survivors who inherit a world washed clean.

Thanks for stopping by for a read.

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved.

Snowball

in and around the lake
Mountains come out of the sky and they stand there

                                              -- Roundabout, Yes

My intent with these writings is to discuss my photography and the resulting workflow. Included in this is my perspective on the subjects I shoot. My primary hunting targets are landscapes, so I’ll be touching on all the issues involved. Weather, planning, composition, hardware, and most importantly, working with light. Being a geologist, I also apply this knowledge in not only choosing where and what to shoot, but also in shaping my viewpoint of my subjects based on my understanding of the physical sciences. I have and will be discussing here the geology that shows up in my images. I hope to build a baseline understanding in my audience of what I am seeing and shooting. What is out there, what it means, and what its history is.

This writing is about what is known as Snowball Earth. This is a period where the Earth was frozen, glaciers scoured the exposed rock in the terrain, and provided the nutrients for the Cambrian explosion.

The Contradiction in Stone

To look for evidence of Snowball Earth is to hunt for contradictions. You find yourself standing in the shimmering heat of Namibia or the scorched emptiness of Death Valley, tripod over your shoulder, looking for the signature of ice. Not the recent ice of the Pleistocene—the stuff of woolly mammoths—but ice of an antiquity so profound it beggars belief. You are looking for a specific type of rock, a chaotic jumble of boulders, pebbles, and sand called a tillite. It is the unmistakable debris left behind when a glacier, nature’s most powerful bulldozer, finally retreats. And you are finding it in places that, some 700 million years ago, were sitting squarely in the tropics. Ice, at sea level, on the equator.

The geologic record does not lie, but it can present a story so outlandish that for decades geologists tried to explain it away. The story it tells is of a planet gone catastrophically wrong. The theory, in its starkest form, suggests that on at least two occasions during a deep-time chapter called the Cryogenian Period, the Earth’s climate system didn’t just falter; it broke. The planet froze over, from the poles to the equator, encasing itself in a shell of ice perhaps a kilometer thick. The oceans became a planetary skating rink. From space, Earth would have been a brilliant, almost featureless white marble.

A Runaway Thermostat

A planet’s climate is a balancing act, a thermostat of sorts. Carbon dioxide in the atmosphere traps heat, while the chemical weathering of rocks on the surface draws that carbon dioxide out. It’s a delicate, self-correcting feedback loop that has, for the most part, kept Earth in the liquid-water-friendly "Goldilocks zone." But in the Cryogenian, something gave the thermostat a hard shove.

The leading culprit was the breakup of the supercontinent Rodinia. This immense landmass was situated mostly along the equator. As it ripped apart, it created new coastlines, dramatically increasing rainfall. Rain, made slightly acidic by atmospheric CO2​, is remarkably good at dissolving silicate rocks. This weathering process pulled enormous quantities of CO2​ from the atmosphere, locking it away in ocean sediments. The thermostat was turned down. And down. And down.

As temperatures fell, ice sheets began to grow from the poles. This is where the second act of the disaster begins: the ice-albedo feedback. Ice is white; it is highly reflective (high albedo). The more of the planet’s surface that is covered in ice, the more sunlight is reflected back into space. Less absorbed sunlight means more cooling, which means more ice, which means more reflection. It is a vicious, positive feedback loop. Once the ice sheets crept down to about 30 degrees latitude, the process became unstoppable. The planet, in a geological instant, snapped frozen.

The Great Thaw and Its Signature

A world encased in ice seems like a permanent condition. With the rocks covered, the chemical weathering that normally removes CO2​ would have ground to a halt. But the planet’s inner heat engine kept churning. Volcanoes, heedless of the frigid surface, continued to puncture the ice, venting gases from the mantle. For millions of years, they puffed CO2​ into the thin, frozen atmosphere. With no planetary sink to absorb it, the CO2​ concentration steadily climbed to levels hundreds of times higher than today.

Eventually, a tipping point was reached. A super-greenhouse effect took hold, and the ice began to melt. And just as the freezing was a runaway process, so was the thaw. The world flipped from a planetary freezer to a sweltering hothouse.

This is the second contradiction the landscape photographer-geologist looks for. Sitting directly on top of the glacial tillites, with no transition, you often find a thick, peculiar layer of limestone. Geologists call them "cap carbonates." Their existence is baffling unless seen through the Snowball lens. They speak of a sudden shift from a glacial environment to a warm, shallow sea saturated with the dissolved carbon dioxide from the atmosphere. To frame a shot of that sharp, distinct boundary—the chaotic glacial mess below and the smooth, layered carbonate above—is to capture the most dramatic climate swing in Earth’s history.

A Fertilized World

The glaciers of Snowball Earth did more than scour the land. As they ground across the continents, they pulverized mountains into rock flour, a potent cocktail of minerals. The great thaw then unleashed this bounty. Acid rain, falling on the freshly scraped continents, washed a torrent of nutrients—especially phosphorus, a key building block for life—into the starved oceans.

The planet, having been put through a deep freeze and a pressure wash, was now a fertilized garden. The stage was set. In the geologic period that immediately follows, the Ediacaran, we see the first fossils of large, multicellular organisms. And shortly after that comes the Cambrian Explosion, a frenzy of evolutionary innovation where nearly all modern animal body plans appeared in a geologic blink. The deep freeze was the crucible in which our distant ancestors were forged.

So when I set up my tripod before an ancient rock face, I am looking at more than just composition and light. I am looking at a narrative. A slab of rock in the desert can tell a story of equatorial glaciers. A limestone layer can speak of a planet that nearly died and, in doing so, paved the way for a world teeming with us.

Thanks for stopping by and having a read.

 

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved.

Uncomforming

 Oh, we won't give in

Let's go living in the past

Oh no, no we won't give in

Let's go living in the past

– Jethro Tull, Living in the Past

“After a time, you stopped tallying the specific hazards.  In its totality, the landscape was predicated on risk.”

To photograph an unconformity is to attempt to capture an image of nothing. You are not shooting a presence but an absence, a record of time that has been erased. It is a subtle and intellectual pursuit, one that begins with understanding the library in which you stand. The Colorado Plateau is that library, a 130,000-square-mile province of flat-lying sedimentary rock lifted thousands of feet into the arid air. The Grand Canyon is its primary archive, a book whose pages are strata, each one once the surface of the Earth. As geologist you know that every single horizon you see was a landscape in its own time. The story is all there, except where it isn't.

An unconformity is a gap in the geologic record. It is a surface, not a layer—a plane of contact where the rock below is vastly older than the rock resting directly upon it. It represents a period of profound erosion or a long spell of non-deposition, a time when the Earth, in this specific place, was taking away rock instead of putting it down. To the photographer with a certain kind of mission, these are the most dramatic scenes on the plateau. They are the scars of lost worlds.

Your eye must be trained to see them. Some are glaringly obvious. An angular unconformity is a story of tectonic violence and subsequent peace. You see tilted layers of rock, the evidence of an ancient mountain range, that have been sheared off perfectly flat, as if by a giant planer. Sitting on that flat surface are horizontal layers, deposited by a later, placid sea. The photograph must capture that relationship: the chaotic, angled energy of the old world capped by the serene horizontality of the new.

A non-conformity is a meeting of two entirely different classes of rock. It is where sedimentary layers—the sandstones, shales, and limestones born of water and wind—come to rest directly upon the igneous or metamorphic basement of the continent itself. This is the Vishnu Schist and Zoroaster Granite at the bottom of the Grand Canyon. To photograph this is to capture the contact between the surface world and the deep, cooked roots of the landmass.

The most difficult to capture is the disconformity, for it is the most subtle. Here, the layers above and below the gap are parallel. There is no tell-tale angle, no dramatic shift in rock type. It appears to be just another bedding plane, another page in the book, except that a geologist has read the fossil record and determined that one hundred million years of history are missing between the two seemingly contiguous layers. Photographing this requires context—capturing the named formations, the Redwall Limestone separated from the Tonto Group, and letting the caption do the heavy lifting. It is an image of a purely intellectual landscape.

To truly tell the story, the photographer must go to the places where these gaps are rendered most starkly. The first destination is, of course, the Grand Canyon, but not just the rim. The work is down in the Inner Gorge. You make your way to Blacktail Canyon, a narrow side canyon off the Colorado River. The source material notes this spot as uniquely accessible. Here, the story is not viewed from a distance of a mile but is available to the touch. The photographer can place one hand on the dark, crystalline Vishnu Schist, rock that is 1.75 billion years old, and the other hand, just inches above, on the coarse, brownish Tapeats Sandstone, which is a mere 525 million years old. More than a billion years of Earth’s history—a quarter of the planet’s entire existence, as some have calculated—is missing in that single handspan. The photographic challenge is to convey this temporal abyss. It is an exercise in texture and light: the way light catches the metamorphic sheen of the schist versus the grainy, sedimentary surface of the sandstone. The resulting image is a portrait of the Great Unconformity, a name given to this specific gap by Clarence Dutton in 1882. Ah yes, Dutton, more about him in a later post.

The Black Canyon of the Gunnison near Montrose, CO. The rock overlaging the basement rock, which forms the canyon, is Dakota Sandstone and Mancos Shale. This same basement rock can be found at the Colorado National Monument. Above the basement rock time is missing, the Mancos unconforms.

From there, the journey continues northeast, to the Colorado National Monument, just outside Grand Junction. Here, the Great Unconformity is, by the numbers, even greater. The time missing spans not 1.2 billion years, but 1.5 billion. The photographer frames a shot of the colorful, banded Chinle Formation—rock laid down some 220 million years ago, when the first dinosaurs were appearing in North America—sitting directly upon the 1.7-billion-year-old Precambrian basement. The story the image tells is of the dawn of the Age of Reptiles resting on the eroded nubs of a world that existed before complex life had even truly begun.

To capture these images is to ask a question: Where did the time go? The running hypothesis points to a global-scale scouring. One theory suggests the breakup of the supercontinent Rodinia initiated a continental, perhaps worldwide, outbreak of erosion. A competing idea is that the glaciers of a “Snowball Earth” ground the continents down to their foundations. In either case, the unconformity is the scar tissue from that planetary trauma. This great erasure, this grinding down of the old world, may have filled the oceans with the chemical building blocks—the phosphorus, the calcium, the iron—that fueled the Cambrian Explosion. The photographer, standing in a quiet canyon, framing a simple line between two different kinds of rock, is capturing the faint, distant echo of the moment the world nearly ended, and in so doing, cleared the stage for everything that was to come.

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved.

Moments

My present work has been to pull together my notes and the literature on unconformities—the gaps in the story, the missing time in the rock. As with any such subject, the approach is to go back over it, to think about the deep time you are trying to 'think about', and to wrestle with the words and phrases that might frame it. You are on a path of discovery, walking terrain that is a cornerstone of the science, missing spaces of time, visited by every student of geology. You are rereading a book with pages known to be torn out, trying to infer the missing chapters. And in the course of this work, while sorting through the knowns and the missing millions of years, as thoughts arrived unannounced, and I wrote them down. I’ll discuss Unconformities another ‘time’.

The is one of a series of images captured about 10 minutes after Sunrise. Memorable because I had also managed to crack several rigs, getting to the spot in the dark.

The sun comes up and the temperature rises. The air warms the metal of the lens barrel, which warms the glass within, and the point of critical focus, once so carefully set in the predawn chill, drifts. You failed to recheck. This is but one of the ticks in the machine you are trying to keep, and its failure can negate all the others. There is the geologic clock, ticking in ten-million-year intervals, its face displayed in the rock before you. There is the sun’s clock, which offers a brief window of slanting, golden light before it hardens into the flat glare of day. And there is your own clock, the investment of hours in preparation and, later, in post-production, trying to true up what you saw with what the sensor recorded.

The whole enterprise is a wager against chaos. Sunrises and sunsets are fickle beasts. You can take the risks—the hike in the dark, the careful setup on an exposed ledge—only to watch the sky lighten behind a solid ceiling of cloud, the sun itself a hidden premise. The light arrives, but not the shadow, not the color. The investment is lost. The enterprise has its physical costs, as well. In Canyonlands, a trip in the dark on the way to a sunrise shoot over the basins ended with a set of cracked ribs, a sharp and lasting reminder of the terrain’s indifference to your schedule. You take the pain. It sharpens the mind. You get the shot.

Sometimes the fault is not in the clouds or the rock but in you. You make mistakes. A technique you weren’t wholly familiar with produces an effect you did not intend. The light was changing too fast—a race you were losing—and in the flurry of adjustments, you failed to protect the highlights, blowing them out to a pure and featureless white. The camera, in these moments, is not an instrument of capture but a theatre of potential failure, its settings a complex grammar you have just misspoken.

Then there are the few times, seared into memory, where the apparatus of consideration simply ceases to function. The workflow, the timing, the careful technical sequence—it all dissolves. You are there to trigger the camera, but the beauty of the scene triggers you instead. It is so complete, so overwhelmingly present, that you forget your purpose. You just watch. The ideal picture forms and then fades, recorded nowhere but in your head. It becomes the fish that got away. You can talk about it, describe its perfection, but the evidence is purely anecdotal, inadmissible. That is a mistake you don’t mind making. It is a failure of the photographer, perhaps, but a success of the human being, who for a moment saw something too profound to be reduced to a digital file.

The passions that drive this are a spectrum. On one end, there is simply a reason for going out into the quiet open spaces, for watching the slow parade of moments as the sun moves the shadows. To be in those moments as the day’s heat fails, to feel the coolness descend as the sun falls, and at the same time to feel the stored warmth of the rock and soil radiating around you. At the other end of the spectrum is the pleasure of manipulating the technology itself, the machine that allows the scene to be brought home.

You have begun recording audio of the environment. It has proven to be a valuable resource, a way to put you back in the moment while editing the captured light. The sounds reconstruct the feeling. The sound of a wing beating the air, a distant crow, the communal chatter of prairie dogs, the high whine of a wave of midges looking for a blood meal. It all serves to recall the specific quality of the light you were seeing, the light you were feeding into the camera.

Moments of pleasure, moments of time. It is all out there, in the rocks. Ages of moments, piled, compressed, buried, stressed, and finally, the old bones of the world exposed as you watch, and capture your own.

Thanks for stopping by and having a read.

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved.

The day in which he wrote about composition

 

“If you never try, you’ll never know” .. Cold Play

A recent run of weather has worked over the backcountry, sending water down arroyos that have been dry for months, rearranging the regolith. The loose mantle of rock and soil shifts, roads are cut, and the landscape, for a time, is made new again. Up high, the aspens are beginning their annual transaction, trading chlorophyll for gold, and down here in the valley the summer’s accumulated heat is slowly migrating out of the rock. You can feel it in the evenings.

The days, meanwhile, have become a litany of what must get done, a list perpetually backfilled by the fine-grained sediment of the day-to-day. In the midst of this, I find a certain enjoyment in returning to the principles of photographic composition, a kind of structured musing. There has always been, for me, a truth in the idea that the surest way to learn something is to prepare to teach it. The exercise forces a clarity, a distillation. It has also sent me down a path of considering my own technique against what are held up as the rules of composition. Not that I operate in defiance of them. As with any practiced craft, the rules don't so much dictate the outcome as inform the workflow. They are the accumulated wisdom against which you test your own eye.

To be your own worst critic is, I suppose, an unlisted but essential part of that workflow. I can look at an image captured and edited a year ago and see only its deficiencies, its failure to communicate. It feels inert. Then I pull up the original RAW file—the flat, uninflected data from the sensor—and remember the distance traveled in post-production, the quiet labor of turning the photograph into what I was seeing, and not necessarily what the camera gave me.

My memory works that way, seeking a certain fidelity to the moment. You pull a black-and-white print from decades ago, and the day it was made comes rushing back, the memory filling in the color, the temperature, the sound—all of the attendant verisimilitude the flat paper could never hold on its own.

Geologic Interlude: Before I begin a review of photographic composition techniques, I'd like to share a New website that has been published. This is an incredibly valuable resource for someone like me, and it aligns with my work here. Its value in general is literally priceless. This is an interactive geologic map, the Cooperative National Geologic Map. This is a product of the United States Geological Survey, USGS, and the American Association of State Geologists, AASG. With this I can zoom into any spot in the continental United States and see the geologic unit at that spot. There are many layers of information, beyond the stratigraphy, available for analysis. This is a treasure. Take a look, and you’ll learn a lot of geology just by interacting with the map. Good stuff! Have a look

https://ngmdb.usgs.gov/nationalgeology/#lat=24.0000&lng=-66.0000&zoom=3&theme=esurf&symbology=synthesis

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Clouds and Cows

To speak of photographic composition is to speak of a language, one that arranges the world within a four-sided frame. At its most fundamental level, it is, as one has said, the “arrangement of elements within a photo to create the desired effect.” But to leave it there is to describe a hammer by only its weight and dimensions. The essence of the thing is in its purpose, which is not merely to make an image “look pleasant” or “good,” but to build a connection. Robert Rodriguez Jr., a photographer who spends a great deal of time thinking about this, puts it plainly: if the composition is careless, the picture will “fail to resonate with the viewer.” It will be a collection of objects, but it will not be a statement.

The discussion often begins with the so-called rules, though they are better understood as creative suggestions, a set of foundational grammars from which one can build. The most famous of these is the Rule of Thirds, a simple tic-tac-toe grid laid over the frame. The theory holds that our eyes are drawn to the intersections of these lines, and placing a subject there lends a natural balance. Sean Gallagher, who has made his living framing the world for National Geographic, confirms its utility. It’s a starting point, a way to avoid the static, bullseye obviousness of dead-centering everything. But it is no guarantee. You can follow the rule and be left with a composition thrown off balance by a vast and meaningless void.

From this basic grid, the language expands. You learn to see leading lines in a curving road or a fence line, guiding the eye into the scene and creating a sense of travel. You find a frame within a frame in a stone arch or a stand of trees, a device that adds depth and isolates your subject from the visual noise of the world. One technique suggests you fill the frame, getting so close to a subject that all distraction is eliminated, creating an intimate connection. Its direct opposite advises using negative space, leaving vast empty areas to give a subject breathing room, to emphasize its solitude against an empty sky. None of these are laws; they are strategies, conscious decisions made in service of an idea.

As the grammar becomes second nature, one begins to explore a more nuanced syntax. You start to understand the inherent energy of a diagonal line, the way it creates a “dynamic composition and tension” that a horizontal placidity lacks. You see the world in terms of patterns—the repeating texture of rock, the ordered ranks of aspens—and you understand the electric effect of breaking that pattern with a single, dissident element. You begin to feel what is called visual weight, the intuitive sense that a dark, heavy object feels unnatural when placed at the top of a frame, creating a subtle unease in the viewer. You might even find your compositions aligning with the mathematical elegance of a Golden Spiral, though as many photographers admit, this is more often discovered in hindsight than constructed by design. It is the result of a practiced eye arriving at a solution that feels correct, a solution that happens to echo a fundamental principle of aesthetics.

The art itself, however, resides less in the catalog of techniques than in the photographer’s process—the quiet work that happens before the shutter is ever pressed and long after the image is captured. It begins with an intentional decision to slow down, to survey a scene and conduct what one photographer calls a “mental inventory” of what you find compelling. What is it here that you love? That question, and its answer, provides the pieces of the puzzle. From there, you move your feet. A small shift in position can straighten a crooked line, separate a tree from a mountain, or reveal a foreground of immense interest. You become vigilant about the edges of your frame, knowing that a stray branch or a clipped object can pull the eye away from your intended focus.

You wait for what is called the decisive moment—the instant a flock of birds enters the frame, or a ray of light breaks through the clouds. This is the culmination of preparation and patience. And the work is still not done. In post-production, a crop can distill the image to its strongest form; a distracting element can be removed. The goal, through it all, is intent. It is the effort to turn the raw data from a sensor into the feeling you had standing in that place at that time. It is a process of learning to see, of developing a visual literacy so deep that it becomes intuition. You are no longer just following rules; you are composing for what matters. 

Composition, then, is an act of translation. It endeavors to communicate not only the particulars of what you see, but the internal resonance you feel from having seen it.

These thoughts are distilled from my own field notes on composition, which I have since formatted and, in a concession to the modern workflow, passed through an artificial intelligence for the sake of clarity. For those interested in a more granular treatment of the subject, a comprehensive PDF of these notes is available. A comment below with your email will find its way to me.

Thanks for stopping by for a read.

All images posted on the buzzshawphoto.blogspot.com 2025 are copyrighted. All rights reserved.