My trip to digital photography.

Twenty years after abandoning my darkroom, an Apple QuickTake camera rekindled my interest in photography. This fixed lens, 320 x 240 pixel camera that managed 16 exposures on its fixed disc memory reminded me about the joy of composition. It took all the variables out of shooting, no exposure changes, no focus, no zoom. I graduated to a 1 megapixel Sony Mavica with a 14x zoom that recorded on floppy disks. I've used a score of cameras since, currently an Olympus E-1.

Looking back, there's not much value in those old images. However, a recent article on Andre Gallant in Outdoor Photographer got me interested in his technique. Basically he sandwiches two slightly overexposed slides of the exact same subject together -- one blurred and one sharp. I did the same in PhotoShop -- with layers, gausian blur, opacity, levels, and unsharp masking -- on some early images I took with the Mavica with some great results.

Still blurry?

Exposure technique in the camera boils down to a choice between two variables: sharpness and stillness.

There is one amount of light that makes your exposure work but two ways to get that light into the camera: the size of the hole and the length of time the hole is open.

These options bear an inverse relationship, that is, as one is lowered the other is raised in order to keep the light entering the camera the same.

F-stops are the way to change the size of the hole, or aperture. The diameter of the hole is represented in the f-stop number as a denominator. The "f" in f-stop is focal length and that will vary from lens to lens, but the formula is always the same, F/2.0, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, etc. As the denominator gets larger the hole gets smaller. And it does so by halves. Each successive f-stop has half the area of the one before. (You can find this to be true by multiplying the square of the numbers by Pi.)

Shutter speeds are how you change the time the hole is open. On older film cameras, the shuttter speed options roughly double, for instance, 1/250, 1/125, 1/60, 1/30 etc., each an increasingly long fraction of a second.

On newer cameras you may have additional stops and speeds but they are inversely proportional on all cameras.

So if you know how much light it takes to make the photograph, you can arrive at that amount in various mixtures of size and speed. Why would you do this and not just take the automatic setting from the camera? Changing your aperture is done principally to change the depth of focus, or the range of sharpness in your composition. Changing your shutter speed changes your your ability to freeze motion or hold the camera still without introducing motion from your own movement.

The smaller the aperture, the longer the range of objects in focus. The faster the shutter, the more likely you can freeze motion.

Often in landscape photography, you want infinite depth of sharpness, so you choose a small aperture and a long shutter speed. To keep the shot still, you need a tripod and no wind. Portraits or close-ups may be better with only a small portion in focus and distracting elements completely blurred into the background. Movement in a waterfall or vehicle may dictate that you intentionally blur portions of your image.

What if you want both depth and stopped motion? To extend your choices, change your capture speed (or ISO equivalent). This resets the light requirement in the camera for your photo and ratchets your shutter speed and aperture ratio to a new point. It's still an inverse relationship but it now works from a point where you might be able to stop motion and get more depth of focus. The trade off, however, is noise or grain. Fast ISO settings tend to introduce more noise in a digital camera because the sensor must work with less light. Less light strains the technology that converts light into an image and mistakes are more common, seen as pixels that are not accurate (color noise) or grain in film.

13. Define order in entropy. Play the odds.

Composition is often the ability to isolate subjects and sort order from natural entropy. Start by assessing your point of interest and ask yourself, “what am I shooting?” Make sure you then capture it.

Watch overlaps between the unrelated objects in the composition. They are often best separated by neutral space. If you have repetition of form or objects, consider how many are in the photo. Given a choice, pick an odd number. People seem to like an odd numbered collection best.

12. Remember the fourth dimension

You think of a camera as a way to make a flat record of what you see. Remember that in addition to height, width, and depth, you are looking at time. Within your photo is the time of day, the time of year and the times you find yourself in. All change your viewpoint.

Being in a place and being in a moment are two intersecting lines that never touch again. You can go back to the place but only ahead to another moment. As Edward Abbey put it, " When I return will it be the same? Will I be the same? Will anything ever be quite the same again? If I return." The camera can preserve our awareness of that intersection of place and time.

11. Sunlight is bleach.

Most people think a cloudless sunny day with the light behind you is best for photography. Actually, this is a very difficult lighting condition. High, top lighting makes too much contrast, too close to the lighted objects. Also watch out for broad areas of brightly lit or near-white colors, they make a distracting foreground.

Your mechanical eye isn’t as versatile as your biological eye—there are simply some lighting conditions beyond your camera's capability. Beware of any situation with more than four f-stops difference within your frame. Shade and sun can be evened out with graduated filters but speckled sunlight near trees pose impossible exposure problems. The light will bleach exposures to the point where the speckled pattern overwhelms the viewer's attention.

To make your photographs “color-safe,” use care in your application of sunlight. Generally, shoot across or into light that’s less than 30 degrees from the horizon. This means your best time to shoot is at the ends of the day. When the sun is near the horizon light has a yellow bias because this part of the spectrum is magnified by the atmosphere it shines through. These warm tones enhance your subject and the light is also less bright. And keep shooting on gray days—they provide perfect diffused lighting for portraits, close ups, and saturated color if you use a polarizer.

10. Weather the landscape.

Perhaps the most overlooked landscape is the ephemeral plane of the clouds. Experimenting with cloudscapes from an airplane makes for endless opportunities. But on land, the wildcard for a scene is often the second scene above—the one that you cannot control or fully anticipate. Capture a cloudscape above a well-known landscape and it’s new again.

9. Capture drama

Photographs that imply an antecedent or a result create mental tension that requires thought to resolve. In short, drama makes images interesting. A passing storm, a crashing wave, a bear and cub, an impossible arch all hint at stories not fully detailed. This is where the expression “a picture is worth a thousand words” came from.

8. Use the painter's eye

To succeed in making memorable images you must see like an impressionist artist. Look at the color components that make up an object. See the color reflected from the water, not just the color of water. (For reflections, look in dark water for lighted objects.) See backlighting of leaves or flower pedals and the reflected light off colored rocks. Notice how the color you might expect is not necessarily there. Tree trunks can be pink at sunset. Water can be copper near sandstone. You can also anticipate how motion will streak your image with color or how light can be visible in mist, fog or smoke.

7. Take away context

Without immediate recognition of context, we tend to see the elements of the composition, like color, texture, shape, size and repetition of form. This can create a novel experience for the viewer, possibly a thought-provoking one. Experimenting with the edges of complete forms—a flower pedal or rock strata, for instance—can lead to the most transcendent nature photographs.

6. Maintain an off-center attitude

My personal theory as to why off-center compositions attract the eye is that we are unable to see off-center on our own. No matter where you look, your focus is in the middle of your view. So the novelty of a scene with the point of interest off-center, which can happen in a camera, delights the eye. I also subscribe to the theory that pure symmetry is the easiest form of composition, one in which we are quickly disinterested. Balanced but asymmetrical compositions draw us into the scene.

Moving the subject off-center will tend to divide the photo into thirds, common advice for composition. The thirds phenomenon is a result, not an objective; it's asymmetrical balance and the off-center attitude that makes the composition work.