Friday, December 23, 2011

Genesis Moment

It is incredibly faint– ghostlike. Moving your gaze about in the dim shrine, you occasionally catch a glimpse of something long gone. Attempting to refocus, you strain your eyes to see something that might not even be there. A certain patience is required to see something so rare as this...

Estate at Le Gras
Support the Nicéphore Niépce House–
© Spéos
Nearly two centuries ago in rural France, Nicéphore (Joseph) Niépce climbed the stairs in the early morning hours into the second story of his family's country estate and set up a scientific experiment, the likes of which the world had never before seen, and which would change the world forever. Just inside the window, he set up a camera obscura consisting of an imaging lens mounted on a wooden box, with a special pewter plate at the rear. He had previously coated the plate with a thin layer of a unique material– bitumen of Judea dissolved in oil of lavender. After carefully focusing the lens, he could easily see on the pewter plate the upside-down, lit image of the roof and farm buildings outside the window.

Nicéphore had previously experimented with such photo-sensitive plates in his successful attempts to reproduce graphical materials (mainly artistic engravings) through the use of light imaged through a lens. Wherever the brightest light of an image struck the special coating on the plate, the bitumen became solid and permanent, forming a long-lasting material image. Now, he sought to reproduce not just simple graphics, but the physical, natural world itself through the medium of light. What an audacious dream– to reproduce what the world looked like, through the agency of nature itself, and without the intervention of an artist's skill and tools! Could such an enterprise be possible? It seemed too good to be true.

Satisfied that the focused image was as clear as possible, he settled back on a wooden chair and girded up his patience, knowing that this would take the entire day. As he waited, the brilliantly sunlit scene outside poured its photonic energy through the window. The scrambled beams of light were precisely redirected and reordered as they pushed their way through the glass lens, finally impinging upon the sensitive surface of the polished metal plate.

Nicéphore continued waiting, eating his lunch while the sun rose high in the French-blue sky overhead. The foreshortened shadows on the ground eventually began to lengthen, and still the photons in the image were building up a physical, material image on the plate. Thin layer upon thin layer of solid, permanent bitumen were formed in the brightest regions of the image.

Hungry again as the sun descended in the west, he supped on bread and sipped on wine, waiting the fullest extent of time for the image that was developing on his plate. Finally, the sun sank below the horizon and he removed the plate from the rear of the box. Working in the dim, golden light of a few oil lamps, he carefully rinsed the surface of the plate with more oil of lavender, hoping to see a real, physical image on the substrate.

He dried the remaining solvent and then examined the plate in the light of the lamps. At first, the metal surface seemed as it had before– simply a shiny gray, metallic gleam. But as he turned and tilted it in the light, something finally caught his eye...was that an image? He couldn't quite decipher what he was looking at until he turned the plate 180°– he had been looking at it upside down, forgetting that the projected image on the plate had been inverted!

Having now seen something that the world outside had not yet imagined,  Nicéphore set himself to refining his process. He began collaborating with Louis Daguerre, who would ultimately stand in the spotlight of public celebrity as the pioneer of photography. Nicéphore Joseph Niépce eventually receded into obscurity, remembered by only a handful who appreciated his foundational role in the invention.

His original photographic plate, containing the image of the estate at Le Gras was given to an admiring botanist and artist in England, Mr. Francis Bauer. Bauer wrote a detailed description on the back of the photograph in both French and English, proclaiming it to be the first artifice "...fixing permanently the image from Nature."

In the mid-twentieth century Niépce had been generally acknowledged as the inventor of photography, although there was no known physical evidence of this work. But Helmut Gernsheim, photographer and photographic historian and collector, and his wife Alison, devoted three years to researching and tracking down such evidence– if it still existed. Tantalizing, obscure references in the literature beckoned them to press on in the pursuit. Through hard work and perseverance they would track the possession of this treasure through at least a half-dozen separate individuals who had owned it through the period of more than a century.

Niépce's "View From the Window at Le Gras"
©, Harry Ransom Center and J. Paul Getty Museum
In February 1952, the culmination of their search took them to the final owner, a Mrs. Pritchard of London, England. Although her family had previously expressed to Gernsheim that the plate had been stolen or otherwise permanently lost from them, it had recently been rediscovered. The long sought image had been found in a dusty old trunk beneath "old clothes, books, and other family relics." A meeting between Mrs. Pritchard and the Gernsheims was at last arranged and they would have the opportunity to see it with their own eyes. As Mrs. Pritchard handed the ornately framed article to Helmut, she expressed her dismay that the image had totally faded away. Looking at the back, he first noticed the clearly worded description of the transaction of this item from Niépce to Bauer. Turning it over, he saw what appeared to be simply a dark, polished metallic plate. But where was the photographic image?

Just as Niépce had done more than a century before, he turned and tilted the plate in the light streaming through the window, until he finally began to see what was there– an image of the country estate at Le Gras, outside the upper floor window. His heart pounded as he realized the fruition of his quest.

Sometime later, the plate passed into his own possession, and eventually into the archives of the Harry Ransom Humanities Research Center, a part of the University of Texas at Austin. The "First Photograph" is currently and permanently on display in the lobby of the Harry Ransom Center.
The First Photograph Shrine,
in the lobby of the Harry Ransom Center

If you possess a serious interest in photography (or the arts and communication in general), and you find yourself in the vicinity of central Texas you should seriously consider a pilgrimage to the Harry Ransom Center in Austin. The Center, itself, is reason enough to visit the area but the "First Photograph" makes it mandatory. This relic is simply the Holy Grail of photography. Like viewing the Declaration of Independence and the U.S. Constitution in the National Archives, this is a unique and memorable experience.

As I reflected in the opening lines of this post, the image is difficult to see and at first glance it appears to be nothing more than a mirror. However, your patience will be rewarded as you find the proper angle to observe it, and Niépce's family estate at Le Gras reveals itself once again. A photograph of this photograph (as can be seen above in the Getty photo) is always less than satisfying, and it can only truly be seen in person. This is an experience that should not be missed.

one of only five complete copies of the Gutenberg Bible
in the United States, Harry Ransom Center lobby
While you are in the lobby of the Center you can view another amazing genesis of modern communication– one of the very few existing complete copies of Gutenberg's printed Bible. This was where printing, as we know it, began so many centuries ago. To see these two incredible inventions in the same room at the same time is a priceless experience.

Finally, read the details of the amazing journey that Helmut and Alison Gernsheim took to rediscover the "First Photograph,"

and discover for yourself the intriguing new finds at Niépce's family estate (and now a photographic museum) in Saint-Loup-de-Varennes, France.

Saturday, December 17, 2011

Christmas Fun

The first day of December I embarked on what has become an interesting photographic project. My daughter recently moved to Kharkiv, Ukraine for a couple of years, to be with her husband who has been running a small software development company there. Since she was going to be out of the U.S. and away from most of her family for much of the holiday seasons, I thought I would attempt to bring some of "home" to her, by way of the internet.

When our daughter was a little girl, growing up in our home, one thing she always looked forward to at Christmas time was the Advent calendars we had. She enjoyed the daily ritual of opening up each day's new "surprise." So, I thought I would come up with my own Advent calendar for her this year, by daily taking a new photo of some little Christmas tidbit around our home, and posting it in a private Christmas Advent page for her somewhere on this blog.

Three Muses Attempt To Stay Warm
This has been a very interesting experiment and project. Each day I have had the challenge before me of how to come up with something entirely new for her. I didn't want to spend a long time composing and taking each shot, but wanted to have something much fresher, and even casual in manner. Some days the resulting photo has been serious in tone, sometimes it has been decidely humorous. But each day, I have tried to produce something that might grab her attention personally, as this project is specifically aimed at her.

It is wonderful every once in a while to take on a photographic project that requires us to stretch ourselves, to do something consistently (maybe even every single day) over an extended period of time. When our subjects are limited but we have to produce something effective anyway, in a very limited amount of time, it can cause us to advance as an artist, and to think and create in modes we might not find otherwise.

Merry Christmas!

Friday, December 16, 2011

Photographic Purity– (Distortion or Not)

Panoramic photographs have their own brand of geometric subtleties (some would call this "distortion"). Much of these effects are because of the extremely wide angle of view (as much as a full 360 degrees) that panoramics rely on. When photography was relegated to capturing a view that simulated looking through a window, the geometry was narrow enough to keep geometric effects below the surface.

As long as a panoramic photo is captured in the "conventional way" (with its plane of rotation parallel to the horizon) so-called distortion is minimal- maybe even undetectible. When that plane begins to tilt away from level, distortion begins to be perceived. If a full 360 view is captured, any planes or lines that are parallel to the horizon appear as a sinusoidal curve.

HARVEST WAVE, © Bill Brockmeier, all rights reserved

This curving of features that otherwise should appear as lines is entirely a consequence of geometry, rather than a deficiency of the imaging system. Imagine that the rotation of a panoramic camera setup sweeps out a cylindrical view of space as it rotates through 360 degrees. If a planar feature in the view (the earth's surface/horizon, for instance) is perpendicular to the cylinder (the rotation is level) the plane will trace out a feature on the cylinder that is a straight line when unwrapped (which is what happens when the pano photograph is printed on a flat sheet of paper).

But if the plane (the horizon) is tilted with respect to the cylindrical view, and the cylinder then unwrapped, you will see that the traced out pattern is now a complete sine curve. The amplitude of the curvature (distance from peak to valley) is a function of the degree of tilt between the plane and the cylinder.

Well, enough on this. I believe I've beaten this dead horse more than sufficiently, and I think you can see that "distortion" is really a matter of personal perspective. What one person might consider a distortion of physical reality is merely one of the myriad (NOTE for Michael: "myriad" is a Greek word meaning, specifically, "ten thousand") ways of reasonably mapping or interpreting the real world onto a finite piece of a two dimensional surface. I don't believe anyone can categorically or authoritatively state that any one particular mapping or interpretation is to be absolutely preferred over another.

I believe it is ultimately important in the arts (of which photography is certainly one) to remember the treachery of images– that the image (the artistic creation) is NOT the reality which inspired it. And it is good to remember that photographic "purity" is more a phantom than a reality...that "distortion" is really the foundation of the photographic arts rather than its bane.

Thursday, December 15, 2011

Photographic Purity– (Building a Panoramic)

We've seen that distortion is built into the process of producing a conventional photographic image. If we take a few regular photographs from the same location, slightly rotating the camera for each frame, we effectively cover a greater field of view with the shots. If the shots slightly overlap each other at the sides, we ought to be able to easily combine  them to produce a single wide-angle image.

Unfortunately, this process will not work because the built-in distortion of the camera lens causes all features in the view to change shape when the camera points in a different direction. When a particular feature is on the right side of the field of view it's one shape, and when on the left side of the field of view it's a slightly different shape. So, when the right side of the first image is overlaid on the left side of the second image, the shapes do not match. This results in either ghost images, missing information, or otherwise mismatched overlaps in the final pano image.

For a proper, undistorted blending of conventional camera shots into a wide angle panorama, the built-in distortion of a standard camera lens must be eliminated, or at least minimized. Once the distortion has been removed the separate frames may be simply overlaid on each other, with the overlapping parts of the images matching well and the images blending into one.
Panoramic sequence of nine frames that have been geometrically remapped to remove camera lens distortion

In the days before modern digital computing, this distortion elimination was nearly an impossible task. Now, this process has become not only possible but even fairly simplistic to the user. Although it seems easy from the outside of the computer, there are actually many billions of calculations and transformations being carried out for a single panorama to be compiled.

Sunday, December 11, 2011

Photographic Purity– (Distortion By Intent)

The whole idea of producing a precisely rectangular  image of a known rectangle in the real world is suspect, and actually a distortion of reality. I say this because a rectangular object cannot truly appear as precisely rectangular.

At first blush this sounds counter-intuitive. You might say: "Of course rectangular objects look rectangular- what else would they look like?!" But do they? Under most circumstances, rectangular objects appear mostly rectangular, but widen the view that a rectangular object encompasses, and the picture becomes clearer.

Imagine that you are standing in front of a very large one story building- let's say that it is 10 feet high, 200 feet wide, and you are 20 feet away from it. The left end of the building stretches way off to the left, and the right end to the right. Those ends of the building appear very small, while the middle of the building right in front of you appears quite large. How then, can the front of the building appear as a rectangle?

In fact, the top of the building and the bottom of the building must actually appear as curved edges, with the two curves farthest apart in the middle, and closer together at the two distant ends. This is a simple consequence of the fact that closer objects appear larger and distant objects appear smaller. For a rectangular object centered on the direct axis of view, this causes all sides of the rectangle to appear slightly bulged out away from the center.

While this scenario is certainly an extreme example, it is still true for all other situations, just to a lesser degree. This is the effect that the built-in distortion in a camera lens attempts to mitigate. This lens design tries to force the object to actually be imaged as a rectangle, when, as we've already seen, it can't really look that way.

For the most part, this purposeful distortion in a camera lens is actually a benefit (why else would lens designers go to such great lengths to design them this way?). But when attempting to reconstruct a panoramic image from separate camera images this built-in distortion makes the effort problematic. I'll look at this issue in my next post.

Image by camera lens with built-in distortion to
produce precisely rectangular shape
View of rectangular object as it might actually
appear as a consequence of geometry

Saturday, December 3, 2011

Photographic Purity– (Geometric Distortion)

Another question that occasionally comes up when people are viewing my art at shows revolves around something they usually refer to as "distortion." The question commonly sounds like this: "I thought that panoramic photos were usually distorted, but these don't look distorted," or: "Is that hill really there, or is that just distortion?" I believe that what they are concerned about is whether or not the photograph looks something like what they would have seen if they had been standing there as I took the photograph.
SEA OF COREOPSIS, © Bill Brockmeier, all rights reserved
The answer to these questions is not a simple one. Much of the problem in answering them stems from the fact that the basis of photography is the attempt to map visible features in the three-dimensional real world onto a finite area, two-dimensional plane. While that may sound simple enough to the uninitiated, it is actually a very complex geometric and human perceptual problem. There is not a single way do to this mapping, but probably dozens of ways, with each method having its own merits and short-comings.

I won't bore you with the details of these dozens of methods, but many of them were devised over the past few centuries as the globe became circumnavigated and every far-flung corner of it became a goal of human exploration. At that time, it became important to be able to precisely represent this three-dimensional sphere we call "earth" on a flat piece of paper, so it could be easily rolled up and carried in a captain's quarters on a ship, or in the saddlebag of a horse-borne explorer. The profession of a cartographer was an incredibly demanding and important job.

When photography came along, this ability to conflate a three-D world down onto a simple two-D representation became an incredibly "easy" transformation to accomplish– automatic, in fact. The photographer didn't even have to think about it, the camera just "did it." But what determined the actual geometric transformation was hidden in the details of the optical system: the precise optical makeup of the lens system and the geometric relationship of the lens to the photosensitive plate (and its shape).

The devising and engineering of optical/lens systems has been a rich field of innovation for the past century and a half. Some of the world's brightest technical minds have been devoted to this pursuit. Their efforts at devising new lens systems have been aimed at things like sharper image focus (better detail), improved light-gathering ability, and decreased geometric distortion– whatever that means.

Lens designers have a very limited definition of what "geometric distortion" (or "image distortion") means. I won't go into what that specific definition is here, but it has very limited significance for most of the photographs that most people take. For instance, if one was trying to exactly reproduce the type on a printed, flat sheet of paper, this narrow view of distortion might be important. But if someone's portrait, or a distant landscape are more likely the subject, it's not clear that this "distortion" is an important consideration.

Most people don't know, and even most photographers don't realize, that most photographic lenses are actually designed with a certain distortion built in. It's easy to demonstrate this with almost any camera, and the more "wide angle" that a lens is, the easier it is to see.

Look through a camera's viewfinder, or at its digital display, and look carefully at some scene before you. Then, start panning the camera to the right. As the camera is in motion you will notice that objects in view will change their shape and size somewhat as they move from the right edge of the frame, to the center, and finally to the left edge. The real objects are obviously NOT changing in shape just because the camera is moving, rather, their image is different because it is passing through the lens in a different direction, thus revealing the lens's built-in distortion.

In both of the photographs below, the camera was placed at a point precisely perpendicular out from the center of the clock. The only difference in the two photos is that in one of them the clock was placed at the right edge of the camera's field-of-view, in the other it was at the left. Notice how the square of tiles immediately surrounding the clock is not square but trapezoidal in nature, and that in one of them the top and bottom lines converge to the left and in the other they converge to the right— their shape has changed. Remember that the location of the camera for each photograph was identical, and that only its direction changed.

clock at right edge of camera's field-of-view
clock at left edge of camera's field-of-view
This distortion is a by-product of the lens designer's determination that if the photographer is taking a photograph of something that is known to most people to be rectangular in nature (and that is fairly far away, and exactly centered on the camera's optical axis, and precisely perpendicular to that axis), the final photographic print should also display a precisely rectangular feature. Although that sounds reasonable enough, this is definitely a distortion of the truth, and, in fact, rectangular objects cannot really appear precisely rectangular, even if the restrictions noted above are followed.

I'll leave the proof of this final assertion for my next entry.