Bikes and Tykes
 

          Every July, the New York Times invariably prints a front-page photograph of Lance Armstrong bicycling by a bright field of sunflowers en route to a Tour de France victory.  The image is spectacular, with the vibrant yellows and greens of the flowers beneath the blue sky, and sleek, colorful bicycles and bicyclists in between.  It's no wonder the Times feels compelled to run a new version of the same picture year after year.  But if you look closely, you'll notice something interesting in the wheels.  They're spinning faster than 30 miles per hour, yet they appear to be frozen still, like a statue. You can see each spoke, as clear as the road beneath it.
          And yet, when you try to photograph your hyperactive three-year-old at his birthday party in your living room, he's nothing but a frustrating blur.
 

          The reason for this is light.  Light is the almighty supreme being that determines the fate of any photograph.  The camera has only a few instruments to control how much light outside the lens may enter the photograph.  The “shutter speed” is how long a period of time the camera lets in light.  Think of a bathtub.  The longer the spigot is open, the more water will be in the tub.  If it's not on long enough, there is no bath.  If it's on too long, the tub will overflow.  If the shutter isn't open long enough, there is no light, and the picture is too dark.  If it's open too long, the light overwhelms the picture, like the outside light blinds you when you leave a matinee.  In each situation, there is some specific amount of light that is perfect, and some amount of time required to capture that perfect amount of light.
          In the agricultural outskirts of Paris, the sun shines brightly on the flowers and bikers.  Only the smallest fraction of a second is necessary.  In one thousandth of a second, a bicycle traveling 30 miles per hour moves just over half an inch.  At close range, you can see an object move an inch, but from across a field, you can see no movement, and neither can the camera.  Everything is still.
          In your living room, sunlight peeks through the window blinds as little Bobby gets ready to blow out the candles.  Yes, there's plenty of light for you to see everything, but for the camera, this isn't nearly as much light as outside.  So it needs more time to let in the requisite amount of light, maybe a quarter or half of a second.  Good luck keeping Bobby still for half a second.  Better luck keeping your hand perfectly still for half a second.  When the camera moves during that time, the whole image moves.  Imagine if Seurat, on one of his pointillist paintings, made not little dabs, but strokes across the canvas.  The result is a blur.
          In your bathtub, you can open or close the spigot to let water either pour or trickle in. In a camera, the aperture (whose measurement is known as the f-stop) determines how large is the opening in the lens that lets light in.  Big opening, lots of light.  Small hole, little light.  If the spigot is open, water gushes in and the tub fills quickly.  If only a trickle is dripping out, the tub will need a good deal of time to fill up.  So it would seem obvious: in low light, open the aperture; in bright light, close it.  But that little round hole has a trick up its sleeve.
          Through the magic of optics, depth of field is also determined by the aperture.  In that bright sunflower field, the aperture is closed tight and everything is in focus: the flowers near the camera, the bikers in the middle, and the horizon behind them.  But at the birthday party, Bobby and all his friends are sitting in a row.  You're at the end of the row, and want to take Bobby's picture.  He's in perfect focus, and spectacularly, everyone's perfectly still.  But no one is in focus but the birthday boy.  His friends in front of and behind him are fuzzy and unidentifiable.  That's because you've opened your aperture to let in as much light as possible.  It's through this same principle that the myopic George Costanza, without his glasses, was able to drive from the Catskills to the Tappan Zee Bridge by squinting.  Smaller opening, sharper image.
 

          So, Bobby's about to blow out the candles.  What can you do?  Professional sports dealt with this problem long ago.  Visit any major league stadium, and you'll see towers of floodlights everywhere.  They aren't there for the players to better see the field, or for the fans in the seats to watch the game; half the lights would be just fine for that.  The extra lights are for the cameras.  Without those lights, on TV, you'd never see the pitcher and the batter in focus at the same time (the open aperture!).  So your first option is to bring every lamp you own, and plug them all in in the same room.  Or open the window shades.  Or use a flash, the bane of photographers.  Imagine that you were the sun.  Everything you see is lit by you.  There are no shadows.  You're not the sun, and this never happens.  With flash, instead of the tykes being lit by the soft light coming through the window, they're being inundated with fake light from the camera.  And furthermore, that light reflects off the kids' retinas, coming back to the camera a bright red, producing an image of a coven of vampires.
          Without flash, there are a few more options.  One easy option is “faster” film.  Film comes in packages usually labeled 100, 200, 400, or 800.  These numbers correspond with the speed at which the chemicals in the film react with light.  200 film reacts with light twice as fast as 100 film.  So instead of trying to shoot Bobby at one quarter of a second with 100 film, you can use 800 film and a speedy 1/32^nd of a second.  Of course, there is a catch.  The faster the film (or the sensor on a digital camera, on which similar adjustments can be made), the more “noise” appears on the image.  On film, this appears as “grain”, better known as proof of the Loch Ness Monster.  On a digital camera, noise comes in the form of colorful specks all over the image, which look fine on wallet-sized thumbnail images, but can ruin a larger print.
          But there is a holy grail: the tripod.  If you're lucky, Bobby might just hold still for a given quarter second.  But for your hand, a quarter second is an eternity, and you'll never avoid the smeared Seurat.  With a hard surface for your camera, that's no longer a problem; just make sure you aren't serving the tots Coca Cola.
 

          Now it is necessary to take a moment to defend fuzziness, which has thus far been thoroughly demonized.  That front-page French landscape might be gorgeous, but, sitting in a newspaper as it is, it misses the most crucial aspect of the picture: the speed and movement of the bicyclists.  In a cartoon, speed lines could trail the racers to indicate motion.  With photography, a longer exposure would more accurately reproduce the pedalers as what they are to the live spectator: a speeding blur.
          Furthermore, sometimes you might want certain parts of a photograph to be out of focus.  At a ballgame, the pitcher stands on the mound, surrounded by the heads of spectators behind him.  The spectators can be distracting, creating a “Where's Waldo” effect, with the pitcher's body blending in with all the fans.  Opening the aperture brings the pitcher into focus and blurs the background.  He becomes, literally, the focal point of the picture, with his uniform and face's sharp edges contrasting with the vaguely defined people in the seats.  Sometimes, you might see the opposite, with the pitcher out of focus to bring the viewer's attention to the excited expressions of the fans.
 

The Ruler of Light

          In Ansel Adams’ famous image of the snow-capped Teton Mountains looming over the Snake River, the sun shines onto the clouds from behind the rocky peaks, and the clouds in turn illuminate the reflective river which flows through the shadowed valley.  This picture is why Ansel Adams is Ansel Adams: to mere mortals, it is an impossible photograph.  It should be accompanied by a disclaimer saying “DO NOT TRY THIS AT HOME.”
          If you're not familiar with Adams's “Tetons and the Snake River,” you may be better acquainted with the Johnsons' “Our Family Picnic at the Lake.”  The kids are playing with the dog, and Mrs. Johnson is sitting at the table putting on sunscreen.  Behind them is a glimmering blue lake surrounded by trees, all beneath a blindingly white slab of sky.  The day was sunny with a clear blue sky, Mr. Johnson insists, but none that is visible in the picture.
          Some of the most beautiful pictures you see are ones that combine light and dark.  So it may seem counterintuitive that the goal of a photographer should be to avoid mixing the two.  The technical term for this paradox is “Dynamic Range.”  Compared to a camera, humans can perceive a wide range of light at a given time.  We can see the yellow sun and the black road, the bride's wedding dress and the groom's tux, the flickering campfire and dark trees.
          The camera can see only a narrow breadth of light in a picture.  Imagine a ruler representing the range of light, from bright to dark.  At the left edge is everything that's as bright as the sun; twelve inches away, the blackness of the total absence of light.  On the sunny day at the lake, the range of light extends from the bright edge of the ruler to the darkish eighth inch.  The sun is at the left edge.  Inch one, the bright sky.  Inch three, the glimmering lake.  Inch four, the Johnson family.  Inch six, the leaves of the green trees.  Inch eight, the shadows throughout the picture.  You can see all of that with your eyes, but the camera can only take three inches of it.  Usually, that three inches will be the family, the trees, and the lake.  The shadows will be black, and the sky will be white.
          With the camera adjusted to the correct settings for the picture's subject (in this case, the Johnsons), if something elsewhere in the frame is too bright, such as the sky, it falls to the left of the three-inch limit, and will be overexposed.  Although less technical, the term used by frustrated photographers is “blown out,” as in, “The sky is totally blown out.”  If part of the image is too dark, such as the shadows under the trees, it is right of the three-inch limit, and will be a dull solid black.
          The key to taking a picture with detailed lights and darks, therefore, is to shoot in situations where the lights and darks are within those theoretical three inches of each other.  Noon on a clear day is bad time: you have eight inches of light.  No terrestrial object is nearly as bright as the omnipresent sun, and few shadows are within the range of the sunlit objects.  Late afternoon, on the other hand, often presents a more condensed range of light.  The sun is lower and its rays are weaker.  If the sun is behind you, the sky to your front is no longer as bright as inch one on the ruler, but now around inch three, closer to the picture's subject, which is still sunlit.  Thick clouds also lessen these harsh effects.  If you're wearing sunscreen, it's probably not the best time to take pictures.
          In hearts and photography, it’s very difficult to shoot the moon.  Night is dark.  The sky is dark.  And at night, the moon is the only thing that’s lit by the sun.  Although a nyctophobe might be heartened by this, it makes life impossible for a photographer.  The sunlit moon and the moonlit earth sit on opposite ends of the ruler, and can virtually never be captured together.  To make matters worse, the moon is more restless than Bobby the hyperactive birthday boy, and moves half its diameter every minute.  So if you need an exposure long enough to let in enough light given the darkness, the moon will keep moving, smearing its way across the image.  Experienced photographers know that the best time to get the moon is very early in the evening, when the sky and the ground are still illuminated by the recently set sun.
          It's always important to know where the light is coming from.  When a man is standing between the camera and a bright window, all you can be sure of is that his back is well lit.  If the light source (the sun, a lamp, a window) is in the picture, it will immediately be overwhelmingly brighter than anything else in the image.  Furthermore, as the light is emanating from a location within the image, it is less likely to be effectively lighting the image's subject.  That said, there is a big difference between the massive thermonuclear reaction of the sun and a 60 watt bulb; the latter is often more forgiving.
          What has modern technology done for this problem?  Very little.  Digital cameras have a narrower dynamic range than film.  A digital camera might have three inches on our ruler; film has closer to five.  An electrified plate of silicon can't handle stress like a silver-coated flap of plastic.  Ansel Adams could get away with things that Captain Megapixel can't even attempt.
 

“I’m Ready For My Close-up”

          There’s a knock on your apartment door.  You’re not expecting anyone.  You peek through the peephole.  And there’s your Aunt Edna, waiting impatiently, with a comically round face.  No, her head hasn’t been inflated like a balloon; the peephole is a fisheye lens.
          Most cameras come not with fisheye lenses, but with zoom lenses, meaning they can be adjusted from a wide to narrow angle of vision; wide for those vacation panoramic shots (zoomed out), narrow for a close-up of the president’s face at a press conference (zoomed in).  The technical term here is “focal length.”  A wide angle has a short focal length, a close-up has a long focal length (and is commonly known as “telephoto”).  The reason for this terminology is, quite simply, that the longer the length of the lens, the narrower the angle of vision.  This is why telescopes are so long: to get very close to the cosmos.  A 50 millimeter camera is the standard; not too close, not too far.  A 35mm lens is a wide angle, and a 70mm is a telephoto.
          What does this technical jargon have to do with Aunt Edna and the peephole?  A fisheye lens is essentially a very-wide angle lens.  And a regular wide angle lens carries many of the same properties, namely, making people’s faces goofy.  One famously conceited actress was known to tell directors, “Don’t come near me with anything less than a hundred millimeter lens!”  Not only is the image rounded (in what’s known as barrel distortion), but depth is exaggerated, and all details at close range are amplified.  Faces will be rounded and have big noses; wrinkly faces will have more texture than Starry Night.  Flattering portraits, therefore, are best shot zoomed in.
          Zooming in tends to isolate the subject.  Its effect is not the same as simply walking in closer.  Right now, look at any object around you.  With your hands, make a square box, and hold it near your eye so you can only see that object.  Now put down your hands and walk to that same object, so that it is as big in your eyes as it was in your hands.  Although it’s the same size, you can see much more around it (because your eyes, like a wide angle lens, are spherical).  A wide angle provides context or unnecessary distractions, depending on the picture.  If you’ve ever seen a Wes Anderson film, you know what a wide-angle world looks like.
          Furthermore, zooming in not only narrows the angle of view, but also the depth of field.  You may recall, a narrow depth of field is when fewer objects are in focus at a given time; the baseball player sharply defined in front of fuzzy bleacher dwellers.  The reason this photo is so common is often not due to an artistic decision, but because the photographer, on the edge of the baseball field, needs to use a telephoto lens to get a close picture of the player.
 

How to be a Photographer: From A to M

          Back when dinosaurs wandered the earth and Jimmy Carter was president, cameras had to be loaded with an antiquated material called ‘film’ made by an old company called ‘Kodak’.  Up to 36 pictures could be recorded on this film, after which you would take it to a store, where they would, after some time, give you paper copies of the pictures.  It was very quaint.
          Today, with digital cameras, you can take hundreds of pictures before the memory card gets full.  It’s a mixed blessing, but it means you can take that many pictures at no cost.  So take all those pictures.  Experiment and make mistakes.  Take ten pictures when you’d normally take one.  Venture from the camera’s ‘A’ to ‘M’; automatic to manual.  Change the shutter speed, the aperture, the ISO, zoom in, zoom out.  Shoot with the sun in front of you, shoot with it behind you.  Take five quick pictures of Bobby, since one might have his signature fleeting grin that your sister keeps describing as ‘devilish’.
          Shifting from Automatic to Manual on a camera is a lot like doing the same thing with a car.  It’s difficult at first, and there will be some occasional stalls (“Stand still, I’m adjusting the aperture!  Don’t move!  Let me tell you a story!”).  Once you get the hang of it, though, it’s a lot more fun, and unlike a car, you won’t need a new clutch after learning.
          The mechanics differ from camera to camera, but generally, there’s a light meter that analyzes the scene, and tells you how your settings need to be adjusted.  On most cameras, there’s an electronic display with row of notches, with a 0 notch in the middle.  If you’re letting too much light in, there will be a mark to the right of the center, and you need to either close the f-stop or shorten the shutter speed until the mark moves to the center.  Similarly, the mark will be to the left if there’s too little light.
          Most cameras have training wheels that provide an intermediate step between automatic and manual: aperture priority and shutter speed priority.  Usually marked Av and Sv (the v stands for value), these settings allow you to adjust one setting while the other setting changes automatically according to the lighting.  So if it’s set to aperture priority, and you decide, “I want to take a picture of my garden, but I don’t want my neighbor’s beer cans to be in focus,” you’ll open the aperture (letting in more light), and the camera will respond by increasing the shutter speed (letting in less light).  In the dark, when shutter speeds generally slow down (and the smeared Seurat becomes an issue), setting the aperture open all the way ensures that the camera chooses the fastest possible shutter speed.
          How does the camera know what is ‘the right amount of light’?  It wants a gray, gray world.  It assumes that, in the three theoretical inches of light it can capture, the average amount of light in the whole picture will be somewhere in the middle.  This is easy if you’re taking pictures of things that are gray.  But what would happen if you took a picture of a bright white wall?  The camera still assumes it’s looking at gray, because the poor thing has no way of knowing better.  The picture that it takes will be too dark.  In those three inches, the wall should be near the bright end, but the camera puts it in the middle.
          Perhaps you’re not very interested in blank white walls.  Snowy scenes present the same issue.  Most of the picture should be a bright white, but the camera wants it to be gray.  And because of this, anything in the picture that isn’t bright white is pushed off the edge of the three inch limit, and will appear a nondescript black.  A bride in a wedding dress standing in front of a black wall presents the opposite problem.
          Photographers deal with this in a number of ways, always in the manual mode.  An experienced photographer with lots of intuition will immediately recognize a scene as brighter or darker than average, and set the camera to take a picture it deems to dark or bright, so the mark on the light meter is not near the center.  An overly-prepared photographer will actually carry around a gray piece of cardboard, aim the camera at it, and set the aperture and shutter speed based on that light reading.
          The most common approach is the one that anyone can do: take lots of pictures.  In a method known as bracketing, you first take the picture the camera wants you to take.  Then you adjust the settings and take a lighter picture.  And then an even lighter picture. And then go the other way; take a dark picture. Then a darker picture.  The idea being, if you throw enough darts, one of them will hit the target.

          Following these directions doesn’t ensure that you won’t take bad pictures. But it makes certain that you will take some good pictures.