Erik Johansson’s imagined worlds

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I read an essay once about writing fantasy fiction.  The key to it was to define a set of rules and then after that to stay true to those rules.  Pigs may fly as long as they always fly.  The worlds that Swedish photographer Erik Johansson’s creates are marvelous fantasies. When you first see them they look quite normal.  Then as your minds eye zooms out to take the whole image in, your sense of the normal becomes challenged, and you start to realize that something is amiss.  Your bed sheet is not made of snow.  Water does not pour from the frames of seascapes.  You can see a collection of his clever images on the msn site or, and perhaps better still, at Johansson’s own website.

I have several favorites, starting with “Stryktalig,” which means “tough” and shows aman ironing his pants and himself.  It is odd because I find myself more troubled by whether the man is burning himself than I am with his gradual transition from being two to three dimensional.  What are we to make of “Wet Dreams on Open Water,” the woman rowing her bed on a lake with floating pillows and an ominous sky?  This is very dark and threatening.  We have been given entrance to someone’s, presumably the woman’s,  private nightmare. “Common Sense Crossing,“the right side up and downside up street is so so reminiscent of M. C. Escher’s famous lithograph “Relativity.”  It raises the same questions about the meaning and reality of topography.

Finally consider another inside out world, that of “Arms break, vases don’t,” Here some one has dropped a vase on the floor.  the vase remains intact, but the person’s arms have shattered, and you worry not so much about the incongruity but rather about the possibility of his cutting his bare feet on the broken shards.  Just when you thought that you understand the world, Erik Johansson has magically altered reality.  Just when you thought that you know the limits of photographic creativity, Johansson has thought outside the box and shattered those very limits!

Kodak to emerge from bankruptcy – it’s not photographic news

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Figure 1 - George Eastman with Kodak #2 Camera on the S.S. Gallia in 1890 by Frederick Church, image from the Wikimedia Commons and in the public domain.

Figure 1 – George Eastman with Kodak #2 Camera on the S.S. Gallia in 1890 by Frederick Church (1864-1925), image from the Wikimedia Commons and in the public domain.

We learned on August 20 that the Eastman Kodak Co, which pioneered the popularization of photography, has earned court approval to emerge from bankruptcy as a  much smaller digital-imaging company specializing in commercial and packaging print.    Big snore!  It’s not photography news.

The name of the Rochester, NY company was for a century synonymous with photography.  They manufactured film, paper, and cameras.  They had development and printing laboratories worldwide.  They made photography accessible to the masses – and parenthetically were responsible for its mediocritization.  Kodak, based in Rochester, New York, was for years synonymous with household cameras and family snapshots.

It seems a paradox that high tech companies like Kodak and the Digital Equipment Corporation were borne of innovation, but then floundered by failing to embrace the next wave.  In Kodak’s case the error was acute, as digital photography was invented by a Kodak engineer.  When Steve Sasson in the applied research laboratory at Eastman Kodak built the first digital camera using a Fairchild CCD, he was told how clever it was, but to keep it all quiet.  The rest as they say is history. The ultimate losers in all of this, needless-to-say, are the Kodak workers, many of whom have lost not only their jobs but their pensions.

Music has charms to soothe a savage breast

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I try very hard not to post about cute, cuddly animal pictures.  There’s enough of that on social media.  However, today I could not resist passing on this wonderful picture by photographer David Gray of Reuters show a leopard seal entranced by the sounds of a saxaphone. The photograph was taken on August 19, 2013at the Taronga Zoo in Sidney, Australia.  IT shows Steve Westnedge, the zoo’s elephant keeper  playing his sax for a Casey, the leopard seal.

It was done as part of a study on the animal’s reactions to sounds. A reader recent commented about cross-species interactions, and I agree that this is really one of the wonderful points about life on planet Earth – that we can interact in a meaningful and mutually conscious manner with other species. In this case the seal occasionally responds with his own sounds.

I am reminded of the famous first line of William Congreve’s “The Mourning Bride,” “Music has charms to soothe a savage breast.” Before I take heat for accusing this soft, warm-blooded, and cuddly leopard seal of having a savage breast, I’d like those of you who haven’t seen or don’t remember the movie “March of the Penguins,”to consider this image by Ben Cranke of Solent News showing a panicked penguin narrowly escaping the gaping jaws of a hungry leopard seal.  The point is well made in the movie “Jurassic Park.”  Animals are not intrinsically good or evil.  They do what they do because they are programmed by nature to do it.  Still as Gray’s picture so poignantly shows they possess the origins of our souls.

 

 

Trilobite eyes – vision in prehistoric seas

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Figure 1 - A schizochroal schizochroal eye of the trilobite Phacops rana, eye dimensions 8mm across by 5.5mm high, found near Sylvania, Ohio, USA, from the Devonian, from the Wikimedia Commons image by Dwergenpaartje and in the public domain under creative commons license.

Figure 1 – A compound schizochroal eye of the trilobite Phacops rana, eye dimensions 8mm across by 5.5mm high, found near Sylvania, Ohio, USA, from the Devonian, from the Wikimedia Commons image by Dwergenpaartje and in the public domain under creative commons license.

On Wednesday we discussed how to correct a lens for spherical aberration: you can use an aspheric shape, you can add a second compensating lens, ideally of a different index of refraction, and you can use a single lens where you grade the index of refraction.  The last of these solutions is the very high tech GRIN lens.  The concept of the GRIN lens is illustrated in Figure 2.  The shape of the lens is a simple cylinder.  However, because the index of refraction changes radially with the kind of parabolic distribution shown on the left, the lens focuses light and corrects for spherical aberration just as if it had a curved surface.

Figure 1 - Schematic of a GRIN lens. Left - the radial distribution of the index of refraction, Right - the cylindrical GRIN lens. From the Wikimedia Commons and in the public domain under creative commons license.

Figure 1 – Schematic of a GRIN lens. Left – the radial distribution of the index of refraction, Right – the cylindrical GRIN lens. From the Wikimedia Commons and in the public domain under creative commons license.

A GRIN lens is not the kind of thing that you expect to see in a prehistoric compound eye.  However, both all three approaches, used today by optical engineers to correct for spherical aberration were employed by nature hundreds of millions of years ago in the construction of trilobite eyes.

Trilobites are a well-known fossil group of extinct marine arthropods that had three part bodies.  They first appeared in the early Cambrian  (521 million years ago), and roamed the seas for the next 270 million years, becoming extinct 250 million years ago.  Those numbers are kind of mind boggling.

Unlike the eyes of modern arthropods which use protein-based lenses, the lens material trilobites utilized was the mineral calcite.  As a result, they are remarkably preserved after hundreds of millions of years and ready for study.  Species such as Crozonaspis used an aspheric lens design that is remarkably similar to that developed by Rene Descartes in the seventeenth century.  Crozonaspis further corrected its lens by addition of an an intralensar body, essentially a second lens element made of a material with a different index of refraction. Most remarkable are the lenses of Phacops rana, see Figure 1 which are actually GRIN lenses, where the calcite, or calcium carbonate, is doped with magnesium carbonate.

It is a remarkable story – complex lens designs created by nature 250 plus million years before Descartes.  The two significant limitations of trilobite eyes, indeed of all compound eyes, is the lack of a means to change focus and the lack of resolution.  This ability to change the eye’s focus is referred to as “adaptation” for human eyes and was first explain by the great British polymath Thomas Young(1773-1829).  In humans this change of focus is accomplished by bending of the lens.  It is, of course, what we do with a camera lens by changing the distance between lens elements or more simply by changing the lens’ distance from the photosensor.  Resolution, as we have seen is largely matter of f-number.

Compound vision

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Figure 3 - Cross section of a pixel on a color digital camera CCD sensor. From the Wikicommons and in the public domain.

Figure 1 – Cross section of a pixel on a color digital camera CCD sensor. From the Wikicommons and in the public domain.

We have been talking about camera lenses, those big objects in the front of your camera that form the image.  But remember that, as we discussed when we considered CCD arrays, that there is a second type of lens in your imaging system.  These are the microlens array (see Figure 1 ) that lie atop the CCD elements. The purpose of these microlenses, you may recall, is not specifically to image but rather to collect as much light as possible and direct it to the photosensitive array elements.  On camera sensor chips there is often considerable dead space and the task of these lens is to collect all this light and bring it to the sensor.  This becomes really essential as you put more and more pixels onto the chip, and you need to maximize the signal because of the limited surface area and well-depth.

Compound Eye of the House FlyThis concept of a sensor element or pixel which reads a single point and outputs a grey level, or color, but not an image, is, of course a copy of compound eyes in nature.  Figure 2 shows a the compound eye of a fly. Figure 3 shows the microlenslet array of the house fly’s eye in a scanning electron microscope.  The compound eye of arthropods provides tremendous field of view and makes the animal very sensitive to motion, as anyone who has tried to swat a fly or mosquito soon realizes.

The situation with the compound insect eye is not quite identical to that of the microlens in a CCD array.  Insects eyes are closer to what would happen if each microlenslet covered several pixels; so that you could form a crude image.  But if you think of that situation light would be coming in from everywhere and each pixel array, called an ommatidium, having a low resolution image of the whole scene.  This is the popular view of movies etc., but not really what happens.  The ommatidia are designed to limit the amount of light coming in from extremen angles.  As a result the image is only of the scene immediately perpendiculr to ommatidium.  So what the insect sees is a tiled view of its world.  Part of the key to all of this is that something that moves between ommatidia is rapidly detected, which is what the insect needs to find food and escape being eaten.

Figure 3 - Scanning electron micrograph of a house fly's eye showing the microlens array. From the Wikimedia Commons by United Nation and in the public domain under creative commons license.

Figure 3 – Scanning electron micrograph of a house fly’s eye showing the microlens array. From the Wikimedia Commons by United Nation and in the public domain under creative commons license.

The resolution of such eyes is however, very limited.  For instance, the resolving power of the honey bee’s eye is only 1/60th that of the human or vertebrate eye.  What a vertebrate can resolve at 60 feet (18 m) the bee can only resolve at a distance of one foot (0.3 m). To see with a resolution comparable to our vertebrate eyes, humans would require compound eyes about 22 m or sixty 70 feet in diameter.  All of this brings to mind Vincent Price as “The Fly, 1958.”  “Phillipe help me!”  Although I have to say that I prefer the 1986 remake with Jeff Goldblum and Geena Davis.

Spherical aberration

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Figure 1 - Spherical aberration, (top) an ideal lens, (bottom) a lens with spherical aberation. From the Wikimedia Commons by Mglg and in the public domain under creative commons license.

Figure 1 – Spherical aberration, (top) an ideal lens, (bottom) a lens with spherical aberation. From the Wikimedia Commons by Mglg and in the public domain under creative commons license.

I know that I have spent a lot of time discussing the issue of image sharpness or resolution.  It is a personal obsession.  Still if you read some of my posts on how a camera works, you may wonder why you can’t just stick a big honking magnifying glass in front of your camera, perhaps add your own toilet paper role to make it light tight, and call it a day.  Or, to put this question differently and to the point, why do we need to spend so many $$$ to get a good camera lens?  The answer to this question ultimately is that you need to correct for lens aberrations.  That’s where all the dollars go, and the first of these to consider is spherical aberration.

Back on September 16, 2012 we talked about Snell’s Law, which describes how light is bent as it moves from one medium, say air with its low index of refraction, into glass with its higher index of refraction, or vice versa.  That, friends, is really all you need to figure out what any lens, regardless of how complex its shape is, will do with light.  There are many computer programs, called ray tracing programs, that can do this for you, including one with the unlikely name of “FRED” that will do this for you, or rather for the optical engineers, who are designing all these wonderful lenses for us.

Figure 2 - A point source as imaged by a system with negative (top), zero (centre), and positive (bottom) spherical aberration. Images to the left are defocused toward the inside, images on the right toward the outside. From the Wikimedia Commons and released into the public domain by mdf.

Figure 2 – A point source as imaged by a system with negative (top), zero (centre), and positive (bottom) spherical aberration. Images to the left are defocused toward the inside, images on the right toward the outside. From the Wikimedia Commons and released into the public domain by mdf.

Suppose, as shown in Figure 1, we consider what will happen to light coming in from far away, aka infinity.  The top panel shows a perfect lens, where all of the rays come to a point focus.  In the bottom panel a ray tracing program has been used to apply Snell’s law of refraction to each ray, taking into account the shape of the lens.  As an aside this lens has one planer surface and one convex surface.  Hence, it is called a plano-convex lens.  What you see happens is that the further off center (the center line is called the optical axis) the ray is the closer to the lens it is focused.  As a result the net affect at the image plane, where the film or camera sensor lies, is that the image gets blurred.

As an aside, the condition shown in Figure 1 is referred to as positive spherical aberration.  The off optical axis rays are bent too much.  With different shaped lenes you can get negative spherical aberration, where the off optical axis rays are bent too little and come to a focus to the right of the image plane.

Figure3 - Example of an aspherical lens shape. From the Wikimedia Commons, originally uploaded by Pfeilhöhe and in the public domain under creative commons license.

Figure3 – Example of an aspherical lens shape. From the Wikimedia Commons, originally uploaded by Pfeilhöhe and in the public domain under creative commons license.

Take a look at Figure 2, which looks at what happens to a point source of light.  Remember that we are interested in points because and image is composed of an infinite number of points – que Seurat Seurat. Here a point source of light is imaged by a system with negative (top), zero (center), and positive (bottom) spherical aberration. Images to the left are defocused toward the inside, images on the right toward the outside.  The blurring of the system due of spherical aberration is clearly seen here.

This raises the question whether you can design a lens to eliminate spherical aberration, that is to be “aspherical?”  The answer is that yes you can, at least for a single wavelength or color.  And happily you can use these same ray tracing programs to design the lens shape and surface for you.  Figure 3 shows an example of an aspherical lens.  You may have seen such shapes before.  This kind of complex aspheric shape is what is used in eyeglasses to correct for spherical aberration.

There are other ways to correct for spherical aberration. One is to use multiple lenses with compensation spherical aberration.  Another is to make the lens of variable or graded index of refraction, by depositing some dopant* into the lens that alters the local index of refraction.  Such a lens is called a GRIN lens for graded index (of refraction) lens.  All of this, I hope, is starting to sound expensive, and we have only corrected for one of many types of lens aberration.

* Dopant is a fancy science word for something added in a small amount.  For instance suppose you made a lens out of calcium carbonate (calcite), you might want to dope it with small amounts, a few percent by weight, of magnesium carbonate.

 

Escape from the Tower of Orthanc

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Figure 1 - The Tower of Orthanc, (c) DE Wolf 2013

Figure 1 – The Tower of Orthanc, (c) DE Wolf 2013

OK, so we are officially in the “Dog Days of Summer.”  Let’s be quite clear about this.  While the term is generally applied to the sultry days of summer, when the temperatures are the hottest, it’s original meaning, and therefore physicist’s meaning, goes back to Roman times when the dog star Sirius rose just before or coincident with the rising of the sun.  It is, in fact, the case that due to what is referred to as precession of the equinox, this coincidental rising is not longer true.  What’s that you say?  The Earth spins on it’s axis like a top.  The top tilts slightly and the axis rotates slowly about the vertical, see Figure 2.  The top was a subject of endless amusement in Dr. Victor Franco’s classes on advanced mechanics.  This precession is also why we declare it to be the “Age of Aquarius,” the sun no longer rising on the day of the vernal equinox in the constellation of Ares, as it did in ancient times but rather in the constellation of Aquarius.

Figure 2 - Precession of a top or gyroscope. From the Wikimedia Commons and in the public domain under creative commons license.

Figure 2 – Precession of a top or gyroscope. From the Wikimedia Commons and in the public domain under creative commons license.

This is a time of wonderful late summer light in New England.  We have effectively seven seasons here, each beautiful in its own right: winter, early spring, late spring, summer, late summer, fall, and winter.  I spotted a wonderful old apple tree in a forgotten orchard meadow.  It was surrounded by gloriously golden lazy Susans.  The light was not what I wanted.  So I have returned four times in early morning, but have yet to find exactly what I am looking for, and now the lazy Susan’s are beginning to give up the ghost.

So, after another disappointing failure with the apple tree, I decided to visit my winter haunt – our local mall – to see what was about.  It is a quiet time in the mall.  Still it is fun to people watch and to search for photographic opportunities.  Mall security can get a bit testy if you snap away with a long telephoto.  But the IPhone provides a degree of anonymity.  It is already fall in the mall, and I observed the various indigenous peoples: beautiful and fashionable women who, since we are in the safety of the ‘burbs, will share a smile with you, long-legged teenage girls who, one can only hope, will find the rest of their clothes before school starts, and babies brought there to be entertained but really delightfully entertaining themselves.  They too are ever ready to share a smile or wave with you.  There are also the sulking teenage boys trying unsuccessfully to look as threatening as possible.  This included one young NY Yankees fan, who wore and A-Rod tee shirt and seemed oblivious to the possibility of abuse by hoards of Boston Red Sox fans.

I wandered past the new Microsoft store.  I was tempted to go in an find out what all the fuss about the “Surface RT” was.  I am a loyal advocate of PC products.  Perhaps it was old geezer prejudice, but there was something not so reassuring about the clerk with aqua blue hair.  I have no problem with dyed hair – but really, aqua!  It seemed a bad fashion decision and did not instil confidence that this woman would know what she was talking about.  Or maybe it had nothing to do with the young woman with blue hair and more to do with years of experience with products that Microsoft assured you that you had to have and then abandoned.

So I moved on.  And then I found it at the altar of the Lego Store, “The Tower of Orthanc!” And there was Gandalf the Grey about to be rescued by eagles.  When you have young children you make the excuse that the magic of such places is to see them again through a child’s eyes.  It is nonsense.  The reality is that you yourself still have a child’s passion, still believe in magic, but are too proud and self-conscious to venture in.  And good thing.  The glorious “Tower of Orthanc” cost $195.  The magic ended there and I bid a hasty retreat town the steps that spelled “Escape from the Tower of Orthanc.”

Figure 3 - Escape from the Tower of Orthanc, (c) DE Wolf 2013

Figure 3 – Escape from the Tower of Orthanc, (c) DE Wolf 2013

 

 

Running of the bulls

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Every year at this time we are greeted (bombarded?) by images of the “running of the bulls.”  One cannot help but feel sorry for the bulls, who seriously would rather be anywhere else.  This fails to mention the point that these primitive mythic games, shades of the Minoan Minotaur and Pablo Picasso, invariably do not work out well for the bovine participants.  Also one cannot help but exclaim something to the effect of “what morons!”

Still, I was struck today by this particularly bizarre photograph by Jesus Diges of EPA/Landov from Aug. 15, 2013, showing the traditional El Pilon bull run at Falces, Spain honoring  of the Virgin of Nieva*. The El Pilon bull run, as can be seen, is held on a very treacherous hill.  Runners have to avoid the bulls on an 800-meter long narrow slope with the mountain on one side and a rather steep cliff on the other.

I pondered a bit, as to what makes this image work against a myriad of other “running of the bulls” pictures.  I think that the first two points that catch your eye are the blood-red shirts and the lone bull, careening down the hill. The red is important because like someone thrilled by an aerialist performing without a net, there is an aspect of perverted voyeurism in all of this!   The broken diagonal of the path creates a dramatic interest.  Indeed, the composition of the photograph is very well done.  The dust tossed up by the bulls and the panicking runners creates a wonderful sense of motion.  The precarious foothold of the observers presents a sense of real danger.  Note in particular the photographer leaning dangerously over the edge to photograph the scene. Also, I find appealing the way the foreground is sharply in focus, while the lone bull and the background fades just slightly to out of focus.  The one aspect that throws the image off is the fellow in the red shirt, who prods the bulls with a rather large stick.  You realize with that, that absent this sadistic, mischievous fellow, the bulls might just stop and graze peacefully on the surrounding grass.  Still, when I first saw this gore-geous image, an immediate caption came to mind. “Uh, oh!”

*Tradition has it that in 1392 the Virgin Mary appeared to a young shepherd, Peter Amador Vázquez, at this spot in Falces.

A note from Hati and Skoll

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(c) DE Wolf 2013

(c) DE Wolf 2013

I wanted to pause and take note of the fact that today is the one year anniversary of Hati and Skoll.  It was launched on August 19, 2012 and we have now built up quite an extensive readership.  I’m talking about real people who visit the site and read the blog each month – not robots, worms, search engines, or webcrawlers.

I have tried to bring my unique physicist/photographer perspective to the site and blog.  The best part of all of this is the opportunity to see in other photographers’ work, both historical and contemporary, the incredibly varied uniqueness of vision.  On day one of Hati and Skoll, I spoke about the magic of photography.  Nowhere is that more apparent than when you marvel at the uniqueness of vision and at how many people are truly gifted.

I believe that digital photography has made it easier to master the technique of photography.  Surprisingly it has not raised the ante.  Rather it has enabled so many to express their souls and inner vision photographically.

So I just wanted to say that I am very grateful to everyone for their interest, support, and perceptive comments.  I have learned from all of you and from all of the pictures that we have discussed.