Archive for June 2014

Single-image Sunday: Moraine Park   11 comments

Moraine Park is a big and very beautiful grassy meadow in Rocky Mountain National Park, Colorado.  I can’t believe this was my first time visiting “Rocky”!  My recent Friday Foto Talk post on dynamic range featured other images from the Colorado Rockies, captured with the Canon S95 I’ve been using lately.

Because of the camera’s limitations, I was hard-pressed to pull off many golden-hour images.  But with the bright, even light of mid-morning at Moraine Park photos were snapshot easy!  I spent a good hour or two just wandering along the creek, drawing closer to several elk who were grazing at the far end.  I didn’t approach them; they have enough people gawking at them in that place!

What a gorgeous day it was!  It was too early for many people.  In fact I was the only walker in the park.  I did encounter a group of horse-back riders from the nearby stables.  The leader was shouting things like “heels down” to the tourists.  Funny!  But also sad when I thought of my horses, so far away (and one of them not even mine anymore!).

The flowers were in bloom as well.  Such a perfect morning, followed by a great hike that traversed the high country in front of the peak pictured.  I will do a travel/hiking post on this national park later in the week.

Hope your weekend was relaxing and fun!  As always, I appreciate any comments.

The Big Thompson River meanders through Moraine Park in Rocky Mountain National Park, Colorado.

The Big Thompson River meanders through Moraine Park in Rocky Mountain National Park, Colorado.

Weekly Foto Talk: Dynamic Range and Realistic Expectations   13 comments

Moraine Park in Rocky Mountain National Park, Colorado.

View from my campsite at Glacier Meadows in Rocky Mountain National Park, Colorado.

I’m a photographer who very much prefers a single capture.  I like to capture a single moment in time.  That’s becoming a somewhat old-fashioned attitude these days, as more and more people do several captures and then blend them into one image using either Photoshop or an HDR plugin.  The reason this technique has become so popular is the same reason that camera manufacturers have been making cameras with the ability to capture high dynamic range.

Images with high overall contrast, those that have perfectly black areas and/or some very bright areas, aren’t so “liked” on the internet as those that have less overall contrast.  It’s an effect of the HDR trend.  Over-the-top HDR images are not popular, but images with a more natural yet still strong HDR effect certainly are!

Shooting into the sun is probably not recommended with a limited camera, but I loved how the sun was hitting this tall grass at Garden of the Gods, Colorado.

Shooting into the sun is probably not recommended with a limited camera, but I’m a sucker for tall grass, especially with the sun hitting it: Garden of the Gods, Colorado.

There is a big distinction to be made between overall contrast and local contrast.  Overall image contrast, though you can certainly adjust it later on the computer, is largely dictated by the scene before you.  Local contrast can be too; it’s definitely affected by the quality of light for example.  But you can “amp-up” local contrast on the computer later, in order to help the image “pop”.  You do this by manipulating the tone curve, concentrating on medium tones.

While images with completely evened-out tones (low local contrast) are not very pleasing and thus unpopular, those with modest overall contrast but high local contrast are wildly popular.  This is especially true in the landscape/nature arena.

Garden of The Gods, Colorado.

Garden of The Gods, Colorado.

Close-up shots like this are a little easier to swing with the little point and shoot.

Close-up shots like this are a little easier to swing with the little point and shoot.

DYNAMIC RANGE

Dynamic range is a fancy-sounding term for a relatively simple concept.  Used originally for audio/hearing, it’s been used in photography since the beginning.  Like everything I write here I’ll try to simplify a topic that if you research it on the web will quickly seem way too complicated to bother with.  Dynamic range is basically the range that your imaging device can capture between the darkest and brightest tones in a scene.  Your eyes are an imaging device of course, and at least in dawn to dusk conditions (for which they evolved) are far superior to the imaging device that you use to share and express your vision of the world – your camera.

You’ve probably noticed this:  Your amazing eyes can detect, at the same time, detail in the darkest and brightest parts of a scene with a high brightness range.  One example is a forest on a sunny day; another is a sunlit barn with a door open to the dim interior.  Shoot a picture of that dappled sunlit forest or barn and you’ll notice your camera has a lot of trouble capturing detail in both the brightest and darkest parts of the scene.  Even the best DSLRs for dynamic range can only capture details in a relatively small portion of the brightness range that your eyes can.

I hiked through Garden of the Gods in Colorado for the first time since I was a kid.

I hiked through Garden of the Gods in Colorado for the first time since I was a kid.  14,114-foot Pikes Peak is in the background.

While you don’t necessarily want high dynamic range in every image you shoot of course, you definitely want to have the option open to you.  If your camera captures a limited dynamic range, it can easily blow out (overexpose with no detail) or block out (underexpose with no detail) parts of the image.  This means you can’t recover that detail; it just isn’t there in the image file.  And so you have the unsatisfactory choice of underexposing or overexposing your image, choosing to show detail in either the darker or brighter parts of the scene.  Or again, you can shoot several exposures with different settings to capture detail in both dark and bright parts of the scene, then merge the images into one on the computer.

Since I generally avoid blending multiple exposures, I’m at a frustrating point.  I am shooting with my little point and shoot camera right now, having lost my Canon 5D Mark III in the waterfall incident.  The little Canon S95 has a small sensor that, while it tries very hard to do the job (it shoots in RAW), cannot capture quite enough dynamic range.

A beautiful pale flower I don't know - like a white lupine - encountered in a meadow in Rocky Mountain National Park.

A beautiful pale flower I don’t know – like a white lupine – encountered in a meadow in Rocky Mountain National Park.

I have photographed with a full-frame DSLR for years now, so I’m used to a different level of expectation.  I’ve been playing on days off in the Colorado Rockies this past week.  And I’ve been shooting the same sorts of scenes and subjects that I was before with my DSLR.  But now I’m blowing out skies, underexposing, and generally messing up.  Worse, I can’t even use graduated neutral density filters to tame the dynamic range; the little lens is just too small.

Since I don’t feel that, with these images from the point and shoot, it’s worth the time spent hand-blending multiple exposures in Photoshop, I’ve been forced mostly to underexpose.  If I instead overexpose I have no way to recover detail in blown-out areas.  The little sensor also shows noise quite easily.  So when I brighten those dark areas later on the computer, I end up with noise, even though I’m shooting at very low ISO.

This has all led to some frustration.  I have been forced to adjust and simply avoid shooting scenes with high contrast.  And I love high-contrast images!  There are many other limitations (the way it handles color for example), but I’ll have to stop here, for fear you all will accuse me of whining.  I will go into more on dynamic range and how to handle it in succeeding posts.  Thanks for reading!

A low-contrast view of Pikes Peak, Colorado.  Add the fact I didn't need great depth of field here, and it's an image my point and shoot can handle.

Low contrast sunset view of Pikes Peak, Colorado. Add the fact I didn’t need great depth of field here, and it’s an image my point and shoot can handle.

 

 

Happy Summer Solstice!   10 comments

Sunrise over Klamath Marsh, south-central Oregon.

Sunrise over Klamath Marsh, south-central Oregon.  Click on image for purchase options.

It is that special day today, Summer Solstice!  It’s the longest day of the year and the first day of summer for the Northern Hemisphere.  For all you Southerners it’s Winter Solstice, the shortest day of the year and start of winter.  For today I’m posting one sunrise, from Klamath Marsh in southern Oregon, and one sunset, from the Pacific Coast just south of the Oregon-California border.

Please let me know if you’re interested in fine-art prints of the images here, or want to buy rights to the high-resolution files.  They’re not available for free download except with my permission.  Please contact me, thanks!

You may already know this but the Earth is tilted on its axis about 23.5 degrees.  This tilt gives us our seasons, and means as we go around the Sun there are four moments (not whole days) when things line up.  In March and again in September there’s a moment when the North Pole is tilted precisely along our path of travel, our orbit, at a perfect right angle to the Sun’s direction.  These are the equinoxes, when day and night are equal the world over.

seasons-earth-orbit_large

In December there’s a moment when the North Pole points directly away from the Sun.  In June, usually on the 21st but sometimes on the 20th, a moment comes when the North Pole points directly toward the Sun.  This puts the Sun as far north in our skies as it can get.  In the Southern Hemisphere it’s low in the sky, leading to short days.  In the Northern Hemisphere it’s high in the sky, leading to long days.

In the far north above the Arctic Circle, where I spent a couple summers a long time ago in Alaska, the Sun never sets at this time of year.  It skims along nicely above the northern horizon throughout the wee hours.  I went on several long hikes in the Brooks Range when I was up there working.  I’m a person who needs darkness to sleep, and I was having trouble staying asleep.  So I used the time to see the midnight sun trace its path across the sky above the Arctic Plain.

Our encampment was down in a valley with a fairly high ridge to the north, so you couldn’t see the midnight sun for about 8 full hours.  It took about an hour and a half to climb the ridge, and I”m sure it would take twice that long for me now!  In good weather there was a clear view out to the Chukchi Sea to the west, the Noatak River Valley to the north.  The glowing sun glided not far above the horizon.

I recall seeing a few grizzlies on their rounds down below.  I never ran into one close, but being alone I was cautious.  I avoided obvious passes and other places a bear might use to cross from one valley to another.

So enjoy our long days all you fellow Northerners.  If you live relatively close to the equator, I’m sorry but all this talk of seasons and change is a bit lost on you.  But heck, go ahead and celebrate with the rest of us!

The rugged Pacific Coast of far northern California witnesses many a fine sunset.

The rugged Pacific Coast of far northern California witnesses many a fine sunset.  Click on image for purchase options.

Friday Foto Talk: Depth of Field III   13 comments

This Friday I’d like to continue with depth of field. But before I do I want to thank all those who contributed to my campaign to replace my camera gear (which tumbled over a waterfall several months back) and get back to showing you all some fresh material on this blog. I will be sending out a reminder email to those folks, to pick the images they want.

I didn’t make it all the way to my goal, but I got partway there. And that means something. I’m busy right now working 7 days/week doing the only thing I know how to do that makes me money quickly. And it’s actually legal, go figure! So it won’t be long before I make up the difference myself.

Make sure and check out the first two parts of this series: Part I and Part II.  They go over the basics behind depth of field.  The example here will show how to apply those basic principles in the field, so it’s important to know them.

Cape Ground Squirrel

I was traveling through Namibia when I took a break from the road.  Namibia is one country in Africa where you can very easily rent a car and take off on an impromptu road trip, like you would in the western U.S.  If the roads in the west were still largely unpaved that is.  

I strolled up a small ridge with my camera and one lens (a 400 mm.).  Suddenly directly ahead this cute little fellow popped his head up and looked at me with big dark eyes.  I had never encountered this rather tall slender rodent before.  Later I found out it was a cape ground squirrel, native to southern Africa.

Of course I wanted a shot of him, and quickly before he decided I wasn’t all that interesting.  But as usual my position wasn’t ideal.  A portion of the scrubby hillside formed the background not far behind him.  My lens only opened up to a maximum aperture of f/5.6.

Since I wanted a portrait that showed him plus a bit of the bare ground at his feet but little else, the hillside was a problem.  It was too close and would have been too much in focus, too distracting.  I wanted as shallow a depth of field as I could get.  But I was limited in what I could do.  I couldn’t open the aperture larger than f/5.6, couldn’t go longer than 400 mm., and couldn’t change lenses.

I was down to one option, changing relative distance between camera to subject and subject to background.  And since I couldn’t move closer without scaring him off, increasing the subject to background distance was all I had.

I grabbed a quick shot or two, in case he ran away. Then I slid down low, lying on my belly so that the hillside behind him was out of view. Now a much more distant ridge formed the background.  Problem was, the lower point of view put my little friend out of view.

So I waited, hoping that his curiosity would get the best of him.  Sure enough he popped his head up again.  Luckily his long tail (which is what fascinated me about him in the first place) trailed to the side.  I had been framing a vertical photo, but I quickly switched to get his tail in and fired off a few frames before he zipped off to continue his daily desert rounds.

The Cape ground squirrel lives in rocky areas of Namibia and South Africa.

The Cape ground squirrel lives in rocky areas of Namibia and South Africa.

I ended up with a pretty good shot of him, a key part of it being the smooth gray out of focus background. The shallow depth of field was afforded by a relatively long focal length of 400 mm. combined with the squirrel’s proximity to me relative to the distance between him and the ridge behind.  The low point of view resulted in the picture’s main weakness, an out of focus rock low in the foreground.

I tend to combine all the factors controlling depth of field (aperture, focal length and positioning).  But since focal length is pretty much dictated by the composition I’m after, aperture and positioning are the main variables.  I’ll move closer or farther from my subject, change point of view to move background forward or back, or ask my subject to move if that’s possible (I haven’t figured out how to speak to animals yet).  All the while I will adjust aperture to the degree that I can.

Of course I run into shutter speed limitations when adjusting aperture.  But it’s easy to mitigate that by adjusting ISO.  Better to have a little noise from a higher ISO than to have a blurry subject because of a shutter speed that is too slow.  I have ruined many a shot because I thought animals or people were perfectly still when they weren’t.  I’ve been a very slow learner in this regard.  Always shoot live subjects at somewhat faster shutter speeds than you think are necessary. 

Friday Foto Talk: Depth of Field II   19 comments

Sometimes quick off the cuff shots are the best. At a small rodeo in Oregon, not only the perfect depth of field, but the expression on this rider’s face was perfect as he looked respectfully at the bull that’d just “had fun” with him.  180 mm., 1/2000 sec. @ f/4.5, ISO 200.

This is the second of a three-part series on depth of field.  Take a look at my 1st one, where some basics are covered.

Depth of field plays a big part in how most images look. Thus it’s important that you are deliberate. I’m not saying be rigid; experiment with different apertures, focal lengths, etc. in order to get different looks. But when it comes time to select your best, when it’s time to decide which pictures you will put out there as representative of your subjects and your photography, then I think you need to take a more conscious approach.

It’s a fact that your choice of depth of field will influence the impact each of your images have. But your choices will also help to set the tone for each of them.  And what’s more, your choices will to some extent collectively influence your photographic style.  It’s like a sort of flow where you select and filter on the way to your unique identity as a photographer.  How you use depth of field is simply one aspect of that.

Along the Kafue River in Zambia, this black-backed barbet had some personality, so I went for shallow depth of field.

Along the Kafue River in Zambia, this black-backed barbet had some things to say, so I went for shallow depth of field.  400 mm., 1/640 sec. @ f/5.6, ISO 200.

Who needs shallow depth of field when you place your subject at the entrance to a relatively dim barn.  This is Gold Dancer, apple of my eye for 8 happy years, who I just had to sell last week.

Who needs shallow depth of field when you place your subject at the entrance to a relatively dim barn. This is Gold Dancer, apple of my eye for 8 happy years, who I just had to sell last week.  121 mm., 1/60 sec. @ f/5.6, ISO 200.

Honey-sellers in Ensenada, Mexico pass the time playing cards.  I wanted to put them only slightly out of focus.

Honey-sellers in Ensenada, Mexico pass the time playing cards. I wanted to put them only slightly out of focus.  28 mm., 1/80 sec. @ f/5.6, ISO 160.

Whatever you do, you should not think of a particular aperture or depth of field as being right or wrong as judged by some imagined body of photography “experts”. It’s not even strictly right or wrong for your subject and conditions.  Rather, it can only be right or wrong based on your particular interpretation of the subject, light, mood, etc.  Trust your instincts and tune out the noise on Facebook etc.

That said, there are some general considerations:

      • Shallow depth of field is used most often to isolate a subject. The photographer wants the viewer to put maximum attention where the focus is and nowhere else. Along with relative brightness, focus is a great way to force a viewer’s eyes to go where you want them to go.
      • Large (deep) depth of field is used to show the whole story. In fact it’s known by many as a “storytelling” aperture. I’m not so sure that you can’t tell a story with an image that has shallow depth of field, but in general giving everything equal weight, focus-wise, facilitates movement of a viewer’s eyes through the scene. How you guide that eye movement is a big part of the art of composition.
      • Moderate depth of field is used when you don’t really have a good reason to go either shallow or deep. When everything in your frame is roughly the same distance away or when your subject is set against a featureless background, you might as well shoot at a medium aperture like f/8. The aperture at which most lenses are at their sharpest is in the f/5.6 to f/8 range.
Two Nicaraguan vaqueros, one of whom I wanted to focus on and the other not totally blur out.

Two Nicaraguan vaqueros, one of whom I wanted to be the focus while the other a supporting character (thus not totally blurred out).  127 mm., 1/250 sec. @ f/4.0, ISO 200.

 

When a large male great curassow stepped out of the jungle at Tikal, Guatemala, I didn’t worry about the fact that I had a messy background that was too close to blur no matter how shallow I went with depth of field.  I just thanked my luck and snapped the picture.  200 mm., 1/60 sec. @ f/5.0, ISO 200.

With this brown pelican in Sian Ka'an, Yucatan, I didn't need to go shallow with depth of field because the sky is featureless and would not distract.

With this brown pelican in Sian Ka’an, Yucatan, I didn’t need to go shallow with depth of field because the sky is featureless and would not distract.  200 mm., 1/2500 sec. @ f/6.3, ISO 200.

There are many ways to play around with depth of field, many ways to create a variety of looks in your images. Add to that all the additional control afforded by post- processing software, where you can simulate any lens effect and more, and you have a plethora of options.  Take it slow is my advice.

It all starts with the capture, and this is where the decisions you make regarding depth of field will make the most difference.  As I laid out in the 1st post in this series, aperture, focal length, positioning and lens choice are all worth adjusting and playing with in a wide variety of photographic situations. Soon enough you’ll know what works for you, and getting the look you want will become quicker and more unconscious.

But don’t let it become too automatic. Depth of field is too important a part of your photography to put on autopilot. Instead it should remain an integral part of your photography’s growth. Learn by shooting and making mistakes, by thinking and reevaluating, by questioning assumptions and yet going with it if it feels right.

Thanks for reading!  Next time we’ll look at an example or two.  All these guidelines are well and good, but how are decisions about depth of field actually applied while shooting in the real world?  Stay tuned.

Mount Hood Oregon and a blooming blue dick, and no way to possibly put them both in focus (without blending 2 shots), so I played around with different depths of field and selected this one.

Mount Hood and a blooming blue dick, with no way to put them both in focus without blending 2 shots.  So I played around with different depths of field and selected this one.  100 mm. (macro lens), 1/20 sec. @ f/32, ISO 160.

Monument Valley's Totem Poles at sundown.  This shot was all about maximizing depth of field.

Monument Valley’s Totem Poles at sundown. This shot, with elements I wanted in focus from the bushes a few feet away all the way out to the moon at a quarter million miles, was all about maximizing depth of field.  28 mm., 1/40 sec. @ f/11, ISO 100.

Travel Theme: Unexpected   15 comments

A really great idea for a travel theme, thanks Ailsa!  Check out all the other entries over on her blog: Where’s My Backpack?.

Maroon Lake in the Colorado Rockies at dawn.

Maroon Lake in the Colorado Rockies at dawn.

Last fall I was shooting sunrise at the ever-popular Maroon Lake in the Colorado Rockies.  As usual I let the other photographers go on their way and lazed around drinking coffee and soaking up some gorgeous sunshine.  I decided to walk down to a little pond near the main lake and look for some abstract or macro shots.  The sun was well up by this time and the light full of contrast.  So I was in no hurry.  I stalled for a few more minutes, cleaning lenses and fiddling with gear.

Maroon Bells in Late Fall I

While I had my back turned a visitor showed up.  When I turned around and saw her, I was surprised to say the least!  I had no idea moose frequented this area.  Change of plan: instead of a lazy stroll, now it was a crouching stalk!  Which was probably not necessary; she didn’t seem too bothered by my presence.  As the last picture shows, she was after a sweet (if soggy) mid-morning snack.  She wasn’t about to let some clumsy human with a camera ruin it either!

The Maroon Bells near Aspen Colorado receive an autumn visitor.

The Maroon Bells near Aspen Colorado receive an autumn visitor.

Water plants, yum!

Water plants, yum!

Weekly Foto Talk: Depth of Field I   8 comments

 

California poppies bloom in an impromptu roadside wildflower garden.

California poppies bloom in an impromptu roadside wildflower garden.  65 mm., 1/60 sec. @ f/13, ISO 200.

Depth of field is one of the most important elements of photography. For most of your captures, you’ll need to more or less consciously control depth of field. You probably already know that aperture is the way to do that. You may also know that it is not the only tool at your disposal. This post will briefly summarize the art of controlling depth of field, then I’ll discuss some of the factors you should consider when choosing depth of field for your images.

What is depth of field? A good working definition goes like this: The extent to which parts of an image are in focus from front (near the camera) to back (far away) is that image’s depth of field.  As you can see it is rather subjective.

Depth of field is often confused with depth, which I posted on awhile back. Giving your images a sense of depth, though related to depth of field, is quite different. Depth is the degree to which you foster the illusion of three dimensions in your two-dimensional pictures. A photograph with good sense of depth, for example, can have a depth of field that is shallow, deep or somewhere in between.

In the northern Guatemala forest, near the ruins of Tikal, a young brown basilisk posed for me while I worked out a good angle for the background depth of field.  200 mm., 1/60 sec. @ f/8, ISO 320.

In the northern Guatemala forest, near the ruins of Tikal, a young brown basilisk posed for me while I worked out a good angle for the background depth of field. 200 mm., 1/60 sec. @ f/8, ISO 320.

A hoary marmot high up on Mount Rainier, Washington.

A hoary marmot high up on Mount Rainier, Washington. 280 mm., 1/1600 sec. @ f/5.6, ISO 200

I wanted this young Himba in a Namibian village to be the star of the picture, but I also wanted the village to be noticed too, so a moderately shallow depth of field was necessary.  68 mm., 1/320 sec. @ f/8, ISO 200.

I wanted this young Himba in a Namibian village to be the star of the picture, but I also wanted the village to be noticed too, so a moderately shallow depth of field was necessary. 68 mm., 1/320 sec. @ f/8, ISO 200.

 

Control depth of field in your images using one or a combination of the following methods:

      • Aperture: Small apertures (big f/numbers) yield greater depth of field, where more of the scene is in clear focus. Large apertures (small f/numbers) give shallow depth of field, where just your subject is in clear focus.
      • Focal Length: The longer the focal length you use, the shallower your depth of field will be. A short focal length (wide angle)will give yield greater depth of field.
      • Relative distance:  To get greater depth of field, increase the distance from you to the closest thing you want in focus. To get shallower depth of field, simply move closer to your subject. That’s the simple way to explain it. Really what you want to do is change the relative distance between you and the subject as compared with the distance between the subject and background. For greater depth of field increase this relative distance. For shallower depth of field decrease the relative distance. See the example images below.
      • The right lens: It may not seem so, but a particular lens’s characteristics can lean the images it produces toward greater or lesser depth of field. This is a minor factor compared with the others, but it’s real. I’m not talking about lenses with large maximum apertures (“fast” with low f/number designations), in order to achieve shallow depth of field. That’s all about factor #1 above.

I’m talking about how some wide-angle lenses allow you to photograph scenes where all is in focus, even if elements are both very close and far away. And how other lenses tend to yield an especially smooth out of focus background, or nicer-looking bokeh (out of focus highlights). Tilt-shift lenses are a somewhat extreme example of lens build influencing focus characteristics. And of course macro lenses have much shallower depths of field than other lenses do (see images below).

A macro shot of the inside of a flower.  Shallow depth of field is virtually guaranteed.    100 mm., 30 sec. @ f/16, ISO 200.

A macro shot of the inside of a flower. Shallow depth of field is virtually guaranteed. 100 mm., 30 sec. @ f/16, ISO 200.

Fairy Bells bloom in the forest with more shade than most flowers prefer.  100 mm., 1/25 sec. @ f/7.1, ISO 400.

Fairy Bells bloom in the forest with more shade than most flowers prefer. 100 mm., 1/25 sec. @ f/7.1, ISO 400.

This will get us going on the discussion.  Please let me know if you have anything to add or any questions.  And if you’re interested in any of my images, whether on here or on my main gallery page, please let me know by contacting me.  I would be happy to honor any request no matter how unusual.  Stay tuned for more on depth of field.  Thanks for reading and have a great week!

My girl, Gold Dancer.  70 mm., 1/1250 sec. @ f/4, ISO 200.

My girl, Gold Dancer. 70 mm., 1/1250 sec. @ f/4, ISO 200.

 

Single-image Sunday: Patterns in Sandstone   5 comments

Since the Foto Talk this week was all about not getting too caught up in the search for abstract patterns in your photography, I thought I’d post an image whose sole aim was to abstract the subject.  But is this really an abstract?  I could have made it more so, for example by moving the camera or otherwise blurring details and color.  Or by getting experimental in post-processing.  But I wanted the close-up features of this dune sandstone to be very clear.

The abstraction is created by simply getting  close with my macro lens and framing so as to exclude the tiny flaws that are scattered through the rock.  I captured this at the famous Wave in southern Utah’s Vermilion Cliffs National Monument.  The sandstone has been worn smooth by water and wind erosion, but up close you can see how rough it is, like sandpaper.

The tiny sand grains are frosted by winds that blew them into dunes during the early Jurassic Period nearly 200 million years ago when this whole region of the American southwest was a vast desert similar to the Sahara of today.

The thin layers (laminae) of alternating color are at an angle to the main sandstone beds.  This is called cross-bedding and is characteristic of dune sands.  The wind blew in grains that had been stained brick-red by iron.  Then it turned around and blew in cleaner, lighter-colored grains from a different source.  These grains would cascade down the steeper lee side of dunes, creating the cross-beds.

The flatter, thicker layers have been eroded into steps, a characteristic of the Wave.  Because of variation in their hardness, their ability to resist erosion, the layers stand out or are recessed.  This differential erosion is caused by variation in the amount and hardness of cement binding the sand grains together.

So what this image shows on a micro-scale is an ancient sand dune in cross-section that is now being sculpted by present-day winds.  In other words, it shows winds in a desert of the distant past, when early dinosaurs roamed the area.  And it shows what the desert of today is doing to those ancient dunes

So an abstract image can tell you something real about the subject.  I believe that’s the best kind of abstract in fact.  I’m hoping the image shows what nature can do, not what me or my camera can do.  Please let me know whether or not I succeeded.  I hope your weekend was a lot of fun.  Thanks for reading.

Undulations

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