And then I bought a camera. A Brownie 127, first of all, with its plastic Dakon lens—a fixed aperture of f/14,* a focal length of 65 mm, and a fixed shutter speed of a fiftieth of a second. I would take the rolls of exposed film to a small drugstore in the Dorset market town of my boarding school, and the chemist there who developed and enlarged the black-and-white images would encourage me, thinking my work had some small merit—or else, more probably, trying to get me to buy some of his small selection of cameras. I eventually caved in to his flattery and bought a 35 mm Voigtländer† camera from him, a decision that sent me on a road that progressed over the years through a long trail of cameras that all used 35 mm film, most of them initially made in Japan by companies such as Pentax, Minolta, Yashica, Olympus, Sony, Nikon, and Canon.
Finally, one day in 1989 in Hong Kong, where I was living at the time, a young Cantonese salesman persuaded me that what I really needed was a quiet, compact, reliable, super-precise, and very sturdy 35 mm film camera that would be suited to my rather unpredictable life as a wandering foreign correspondent. A Leica M6, he said, and equipped with a remarkable lens, a (then-unfamiliar to me, but already legendary to those in the know) little black cylinder of robust delicacy, the phenomenally light and extraordinarily fast confection of air, glass, and aluminum known as the 35 mm f/1.4 Summilux.
That little lens stayed with me, performing journeyman work for the newspapers and magazines for which I worked, for more than a quarter of a century. It then went on to serve briefly on a newer and very different Leica body that I acquired much later. Eventually, I succumbed to the advice of my betters and bought that lens’s natural successor, the 35 mm f/1.4 Summilux ASPH, which had an aspherical lens with what is called a floating element to it—regarded at the time of this writing as perhaps the best general-purpose wide-angle camera lens in the world, and probably the classic popular exemplar of high-precision optics.
There are certain ineradicable truths in the world of optical hyperprecision, and one of them, by near-universal agreement, is that the best Leica lenses are and long have been of unsurpassed quality, and deservedly represent the cynosure of the optical arts. The century-long arc of progress began with the moment in 1913 when Oskar Barnack—legend has it that he was asthmatic, and needed a lightweight camera—made both the first 35 mm film and then the first-ever Leica camera, called the Ur-Leica. It led to the creation of the supremely good lenses of today, a trajectory of progress in optics that mirrors much of the progress of precision more generally, even though using materials that, unlike most of the devices in this account, are invariably, and for the best results, transparent.
The optical journey itself begins almost a century earlier still.
If humankind’s acceptance of light and dark began the moment the first eye was opened, or blinked, or shut, then the first questioning of optical phenomena probably started soon thereafter. The nature of shadows, of reflections, of rainbows, of the bending of sticks in pools of water, of shades and tint and hues of color—all would have come first, and then later there would have been considerations of the action of mirrors, of burning glasses, of the twinkling of stars and the steady light of planets, of the anatomy of the eye—all inquiries that are recorded in writings (Greek, Sumerian, Egyptian, Chinese) from at least three thousand years ago. Euclid’s Optics was written in 300 BC, and though it is mainly a treatise on the geometry of angular perspective, and the belief that light to the eye is created by an ether-like substance called “visual fire,” it laid the groundwork for Ptolemy’s theories of five centuries later, brought some detachment and sophistication to the science of astronomy, and advanced theories of refraction and reflection that have not changed much to this day.
The prototype Ur-Leica, fashioned in 1913 by the Leitz employee Oskar Barnack. It was small, light, with a near-silent shutter, and a 24 × 36 mm film format.
Surgery on eyeballs had already revealed the existence of a lens, a perspicillum, which, from its secure position at the front of the iris, magnifies all that it sees. It was a Swiss doctor who first displayed the lens of the human eye, and gave it the name that Romans had for centuries given to the small pieces of glass that the optically afflicted used for helping with their poor vision: perspicillum in later years denoted either a telescope, to see distant things up close, or crudely made and ad hoc spectacles, which helped make close things appear sharply in focus and the illegible capable of being read.
Even though Ernst Leitz famously helped his Jewish employees to leave Germany in droves, his cameras were much used by Hitler’s military. Here are a pair of IIIcs worn by a Kriegsmarine seaman.
Nero, myopic in more ways than one, was said to have watched gladiatorial contests through a conveniently curved emerald. The first true spectacles appear in images drawn in Italy in the thirteenth century, with simple lenses maybe, but life-changing for those who required them or for uses that allowed for the discovery of the distant unknown. Then came Galileo, and Kepler and Newton, and theories of light became ever more complex, and the exactitudes of geometrical optics took over from a hazy belief in visual fire; and then telescopes and binoculars and microscopes were made; and Benjamin Franklin reputedly created bifocal lenses, the glass more convex in his spectacles’ lower half for reading and less rounded above a metal spacer, and so allowing for viewing at distance, in the early 1780s or, maybe, according to new research, as much as fifty years before that. Finally, in due time, with the realization of light sensitivity among various families of chemicals, the scientist and inventor Nicéphore Niépce snapped the first photograph and preserved one modest illuminated moment (even though it was a moment no less banal than its title, A View from the Window at Le Gras) for all time.
Snapped is hardly the word. Niépce used a camera obscura, at the back of which he mounted a pewter plate he had painted with a thin layer of a kind of bitumen he had discovered would harden upon exposure to light, becoming less hard in those places where the lens directed the lesser light and firmer where the illumination was intense. The asphalt was also selectively soluble—it could be washed away with a mixture of lavender oil and white gasoline—and Niépce realized with decisive logic that the firm parts would likely be more resistant to washing and the softer parts easily swept away. So, using this kind of chemical reaction to light and dark, Niépce took a photograph. It was a crude picture of a rooftop terrace made of blocks of stone, with a grove of trees at center stage and, across slightly to the right, a distant horizon with steeples and vague outlines of hills. It is barely recognizable, yet it is undeniably a vague image of just what his primitive little camera saw.
The picture was taken in the summer of 1826, in an east-central French village named Saint-Loup-de-Varennes (now a place of pilgrimage among the world’s photographers), and with an exposure time of many hours, perhaps even many days. There is nothing either precise or accurate about the image, though it has a strangely ethereal beauty to it, and is viewed with great and deserved reverence in a vitrine in a much-protected vault at the University of Texas at Austin.
We know less than we might wish of the kind of lens Niépce employed on that long-vanished sultry summer’s day—was it made of rough or polished glass, of ground crystal, or of a piece of amber found in a riverbed? We can suppose, but we cannot be sure. It was certainly fixed solidly in the camera box, and was certainly composed of just a single element, a single transparent entity. It was probably lemon shaped, convex on both sides. From examining the image that resulted, we know that it suffered from all the classic limitations of early photography: an inability to focus being one, an inability to capture sufficient light another, with distortions at the edges and at the sites where more light was falling. It certainly had no pretensions to being precise. Yet it is quite rightly a piece of deliberate creation, the haunting nature of its imagery a foreshadowing of a whole new art form to come.
Since Niépce’s pioneering work, lens designers have discovered a host of technical problems that can con
spire to spoil a photographic image: chromatic aberration, spherical aberration, vignetting, coma, astigmatism, field curvature, and problems with bokeh* and the so-called circle of confusion being among the best known. They have therefore experimented endlessly to produce compound lenses of great complexity that correct for all these trials but that are at the same time fast and light and pure and true, and that contrive to make images that are as close to technical perfection as it is possible to imagine. The 134-year journey from Niépce’s creation in 1826 to the designers and makers who created Leica’s first 35 mm f/1.4 Summilux lens in 1960 offers a demonstration of a great optical trajectory, from simplicity to high precision, marking a passage in time from which all images were necessarily vague, to today, when, if desired, all can be razor sharp—not necessarily more beautiful, but forensically useful, in which highly detailed and accurate records of moments in time can be produced and preserved, and which, because of their accuracy, are entirely amenable to being blown up many, many times.
The way in which this was achieved has as much to do with mathematics as it has to do with materials. Mathematical concepts such as angles are crucial—angles of refraction, for example, or angles of dispersion, both of which are determined in large part by the kind of glass used in a lens. Refraction is a measure of how much a lens bends light, dispersion of how varied are the angles at which a lens refracts light of different wavelengths (that is, of different colors). Early lens designers did their best to limit spherical aberration and chromatic aberration (the very visible consequences of too much refraction and too much dispersion) by the brilliant idea of grinding two lenses of different materials such that they fitted exactly together—and in doing so, in the late 1830s, they created the first kind of multi-element lenses.*
The multi-element arrangements that followed, and that have dominated fine lens making ever since, began primitively enough, with just the two lenses pressed together. In these early examples, one lens would be made of a glass with specific refractive properties, such as so-called crown glass, which has a very low refractive index; and the other would be made of so-called flint glass, which has a very different chemistry, a high refractive index, and very low dispersion. Grind them into complementary shapes and press and cement the two together, and you come up with what is called a doublet.
The illuminated image whose reflected rays pass through this doublet are then focused onto the film at the back of the camera in a manner that will be much more disciplined, focused, and lifelike than the fuzzy, blurred-edge, and randomly aberrant imagery previously offered by single-lens cameras of yore. The crown glass lens deals with one problem, the flint glass lens with another—and the two together are ground so perfectly that, optically, they act as one, with one physical effect on the light, variously now tinkered with by its two components.
Multi-element confections of one kind or another have dominated good-quality camera lens designs ever since. Optics designers are today rather like orchestral conductors, maestros who marshal and corral morsels of carefully shaped and exquisitely ground glass of varying chemistries and optical properties into configurations that will provide the most harmonic and pleasing management of light for the task the lens is designed to perform. Lens geometries are infinitely variable, lens materials even more so—tiny additions of rare earths change the dispersion and the absorption and the refractive abilities of transparent materials, while certain nonglass materials (germanium, zinc selenide, fused silica) perform particularly well with certain kinds and wavelengths and intensities of light.
The job of a lens is to capture the light and present it to the camera and the film or the sensor it holds. As cameras and films and sensors became ever more able (allowing for higher shutter speeds and finer grains and, in the digital world, ever more pixels), the manufacture of light-presenting lenses became ever more demanding, the arrangement of glasses within ever more intricate. Portrait lenses, for example, had one kind of configuration: an early kind had four lens elements, two cemented together, two grouped together but with air sandwiched between them. Lenses designed for capturing photographs of landscapes, for their part, had very different arrangements, as did wide-angle, close-up, telephoto, macro, fish-eye, and zoom lenses. Indeed, some variable zoom lenses have as many as sixteen elements, some of them movable, some of them fixed, some stuck firmly together, and some separated by distances large enough, but nonetheless very accurately measured, for the resulting lenses to be of bewildering and barely manageable lengths, often needing a tripod support of their own, with the camera body a mere bagatelle fixed to one end.
Leica—the name is a blend of the company founder’s surname, Leitz, and his product, a camera—entered the field of exact optics in 1924. The inventor of the first 35 mm camera, Oskar Barnack, whose two Ur-Leicas were built in 1913 and whose O-series production camera was offered to the public in 1925 (the interlude being due, of course, to the Great War), was incredulous at the quality of the early lenses. The O series was equipped with a lens designed by a long-forgotten optical genius named Max Berek. It had five glass elements (a cemented triplet and two singlets), and when Barnack saw the results, a clutch of eight-by-ten-inch prints sent to him in the mail, he dismissed them out of hand: they couldn’t possibly be the enlargements of the 35 mm images he had been promised. Yet, of course, they were—blown up tenfold and losing none of their crispness in the process. The lens that took the images went on the market as the 50 mm Elmar Anastigmat, and it remained a classic for generations, and is a priceless collector’s item today.
And down the years, so the lenses processed, all with code names ineradicably linked with Leica: the Elmax, the Angulon, the Noctilux, the Summarex, the too-numerous-to-count Summicrons, and the bijoux of the family: the three focal-length superfast lenses (35 mm, 50 mm, and 75 mm) that were given the code name Summilux, and all of which were designed to offer the most stringent accuracy even at their widest aperture of f/1.4.
For the making of all these, the common Leica standards were unparalleled. Whereas most camera makers work today to an industry standard of 1/1,000 of an inch, and with Canon and Nikon working their mechanicals to a supertight 1/1,500 of an inch, Leica bodies are made to 1/100 of a millimeter, or 1/2,500 of an inch. And with lenses, the tolerances are even tighter. The refractive index of Leica optical glassware is computed to ±0.0002 percent; the dispersion figures (the so-called Abbe numbers) are measured to ±0.2 percent, against an industry-agreed international standard of 0.8 percent. And the mechanical polishing and grinding of the lenses themselves are performed to one-quarter lambda, or one-quarter of the wavelength of light, with lens surfaces machined to tolerances of 500 nanometers, or 0.0005 mm. And with the aspherical lenses that cut so markedly down on the tendency at wide apertures to display spherical aberrations, machining of the glass surfaces is performed down to a measurable 0.03 micrometer, or 0.00003 mm.
The lens I now have as successor, the mighty miniature classic 35 mm f/1.4 Summilux, ticks all these boxes, insofar as it now comes with one aspherical lens element that has, in a very recent iteration known as the aspherical FLE, four of its nine elements closest to the camera body floating, free to travel together as one within the lens structure, giving the most memorably good results. This lens has become perhaps the best-regarded wide-angle piece of optical glassware ever made, by anyone: the reviews have been stellar.
To hold one of these lenses (a scant ten ounces of aluminum, glass, and air) is to hold almost the most precise of modern consumer durables—with one notable and rather obvious exception: the smartphone. Within that particular handheld device (as I shall outline later) is a sturdy mix of mechanical exactitude, the various component parts finished to the severest of tolerances. Yet there is also, and essentially, a mass of electronic precision to it, a gathering of myriad components where no moving parts are present to interfere with what is designed to be their constant perfect performance. The making of the circuitry that runs the smartphone, and similar versions
of which run other devices big and small that profoundly affect so very much of today’s lives, takes the concepts of accuracy and precision into a whole new realm. But that is for later.
MECHANICAL PRECISION, AT this high and demanding level, can on occasion stumble, however—tiny errors can be made; they can accumulate, resonate, and harmonize to become major errors, after which they can become the origin of problems that the designers may never have supposed or imagined.
For instance, those workers in Hucknall, Nottinghamshire, who in 2009 incorrectly machined the tiny metal tubes made to lubricate the turbine section of a jet engine never would have imagined that, a year later, because of their minuscule mistake, a fire would break out, the engine would destroy itself, and the lives of almost 470 people would be briefly in the balance a mile up in the sky above Indonesia.
The kind of tolerances demanded in modern precision devices allow essentially for no errors, but insofar as human beings are still involved in the manufacturing of precise things, human failings do occasionally creep into the process. Possibly the most recent classic example of an imprecise human failing intersecting with a mechanism made for a precise and uninhabited world was that exposed for all to see with the launch, and then the failure and, finally, the great success, of the Hubble Space Telescope.
“ASK ANY PERSON the name of a playwright,” remarked Mario Livio, a NASA astrophysicist and senior scientist on the telescope project, “and most of them would say Shakespeare. Ask them the name of a scientist, most of them would say Einstein. Ask the name of a telescope—they will all say Hubble.”* There is a distinct public reverence for this telescope, in part because of the sheer magnificence of the images it has sent back to Earth from space in recent years. To some of us, though, Hubble is perhaps also regarded fondly because of its vulnerability, because of its troubled story, its phoenixlike rise from the ashes of its awful beginnings.