Shutterfinger

Four Tips for Great Portraits

You can tell I used a large softbox to light this by the highlights in her eyes. The reflector opposite the softbox is less obvious. I placed it just close enough to keep the keep the shadows open but not so close that I would lose the three-dimensionality of the lighting.

Even though the bulk of the photos I shoot these days are candids and street photography, I can shoot a professional quality portrait when the need arises. In the even that you get called upon to shoot one yourself--for a friend's LinkedIn page or website for example--or you'd simply like to improve your portrait skills, here are a few tips that should come in handy.

1. Think about the background first.

In a classic headshot your subject is in the foreground while the background is, well, somewhere in back. It's generally best to choose a background that has neutral color, tone, or pattern; one that won't visually merge with your subject, yet not so bright and colorful that it becomes a distraction. A pure white background can work as long as it's not so bright that it causes lens flare.

Also think about the distance between your subject and the background. The greater the separation between the subject and background the greater your ability to use depth-of-field to control how in focus the background will be. A telephoto lens and a wide aperture can do wonders to blur away a distracting background. Separation between the subject and background also allows you the option of lighting or shading the background separate from the subject and thereby prevent tonal mergers.

2. Start with one light, preferably large and close.

A common mistake portait beginners make is to overlight the subject. There are too many lights coming from too many different directions and most of them wrong. I find it's a lot easier to get the light right when you start with one light and then move either the light or the subject until the highlights and shadows look good to the eye. This obviously takes some judgement and the best position with vary with the subject. Generally speaking, you want the light off to one side or the other, otherwise the lighting will look flat and one-dimensional. You also want to raise it a bit, so there's a slight shadow under the nose.

The size of the light and how close it is to the subject will determine how soft and diffuse the light will appear. If I'm using a 42-inch diameter umbrella or a 48-inch wide softbox  I generally place it no further away than 36-inches from the subject. If I'm a large, north-facing window, I place the subject as close as possible without getting the window into the photo.

Here the light source is smaller and the shadows darker. There is still some light filling in the shadows though, as you can see from the detail in her black shirt. As with the first photo, the background was a simple roll of white backdrop paper, lit to reproduce as a shade brighter than her skin.

3. Fill in the shadows to taste.

If you use one light you will have one shadow area. How dark it is will depend on the general reflectivity of the room or the area you're in. If you're shooting digital you have the luxury of being able to tell right away just how dark the shadows appear in a photograph. If the shadows are too dark, place a large white reflector, such as a piece of foamcore or matteboard, opposite your light source. The closer and/or brighter the reflector, the lighter the shadows will be. If you're looking for darker shadows, try a sheet of black foamcore or matteboard.

4. Be relaxed and relax your subject.

Remember that you're dealing with a human being, not an inanimate object with no insecurities and limitless patience. The more attention you pay to making your subject feel relaxed and confident, the more these feelings will show in their expressions. Even the most beautiful and "perfect" lighting will be wasted if your subject looks tense, confused, apprehensive, or annoyed. So keep the mood light. A few compliments, a few jokes, a few clear directions ("Turn your face toward the light a bit. Ah! That's it. Perfect.") and frequent clicks of the shutter when everything falls into place will do wonders for their confidence and yours.

Dozens of photographers have written entire books on the subject of how to light and pose portraits, so there's obviously more to learn than just these four tips. Nevertheless, if I were to boil what I've learned down to just four tips, these would be them. The rest is just practice, experience, knowing what you're look for, and paying close attention to what you see happening in front of you. If any of you have anything of value to add, either advisory or precautionary, feel free to add a short comment. None of us, myself included, knows so much that we can't learn a thing or two.

How Low Can You Go?

 

Is this photo perfectly sharp? No, but to my eyes it's acceptably sharp--especially since I shot it with a 10omm Series E Nikkor lens at f/2.8 and 1/50 second at ISO 800. That's about as low as I'm willing to go. How about you?

These days practically anybody can get a nice, sharp, well-exposed photograph in broad daylight. Set the camera to auto-everything and the algorithms will take care of the rest. It's when the light gets dim that mastery, skill, and yes, sheer luck come to the fore. 

Consider this: In low light--and by "low" I mean light that requires you to shoot at or near maximum aperture AND at a shutter speed below 1/60 second AND at an ISO above 400--you are dancing on the razor's edge of technical quality.

Let's start with the optical challenges. Most lenses are least sharp and contrasty when shot at maximum aperture, especially at the corners of the frame. Another issue is that you have less depth-of-field at maximum aperture, so your focus needs to be spot-on, yet low light is exactly the point at which most AF systems begin to struggle.

Next are the challenges related to camera and subject motion. If you're using a camera or lens that has image-stabilization you have the luxury of being able to shoot at a shutter speed at least two or three stops slower than otherwise. Unfortunately, many of such cameras and lenses have a maximum aperture of f/3.5 at best and f/5.6 at worst, so you're often forced to shoot at slower shutter speeds than you might otherwise. Slow maximum apertures reduce your depth-of-field problems while increasing problems with subject motion. It doesn't do much good if you can hold your camera steady at 1/8-second if your subject is in constant motion.

"No problem," you say, "I'll just crank up the ISO." Your success with the approach will, of course, depend on what type of camera you're using. If you're using a camera of recent vintage with a full-frame sensor you can use ISOs as high as 3200 and 6400 with relative impunity. If you're using a camera with a small sensor, the increase in image noise and loss of resolution can get grim even at ISO 800.

Just for comparision, here's a photo shot at the same ISO (800), but with a 35mm lens at f/2.8 and the shutter at 1/100 second. It's significantly sharper than the photo above. Does this make it a better photograph? I'll let you be the judge.

The final factor is this equation is you, hence the title of this post. How low a shutter speed can you shoot at hand-held and still get results you considerable acceptable with reasonable consistency? In my case it's 1/30 second with no image stabilization, two stops slower with it, and only as long as the lens has a focal length no more than 50mm. I'll shoot at maximum aperture if I have to, but even in low light I prefer to stop down a bit, especially if the maximum aperture is a generous f/1.4. As for ISO, 1600 is generally my upper limit. I find that once I go past that the image gets "fragile," with a lot less tolerance for color and contrast curve adjustments.

All of these self-imposed limits are towards the goal of producing what I would consider to be an acceptable 8x10-inch print--not truly and completely sharp, mind you, just acceptably sharp. Your standards might well be higher if you want larger prints or lower if you only need small JPEGs for screen display. Whatever your standards, don't assume thatbecause you've got great technique in bright light that it will automatically transfer to shooting handheld in low light. The only way to get good at it is to do it and see for yourself just how low you can go before you either have to use a tripod, add supplementary lighting, or give up.

So, just out of curiosity, my question for today is, how low can you go? How low a shutter speed? How high an ISO? How long a lens? And how reliably sharp are your results?

 

Simple Themes Are Often the Best

 

 

Photo courtesy of Adrian Fisk - iSpeak Global

I was surfing the web a few days ago, looking for photography-related topics to amuse and educate myself, when I came across this. If you want to know what you'll see before you click the link, it regards Adrian Fisk, a UK-based photojournalist who has created a project called iSpeak, which he began in China and has expanded into India.

The iSpeak concept is simple: Fisk finds young people from different walks of life, gives them a blank sheet of paper, tells them to print whatever they would like to express on it, then photographs them holding their words up to the camera. Some write in English, others in their native language. For those who are illiterate, Fisk photographs them holding a blank sheet of paper and provides a caption that expresses what it is they want to say. Even though his motif is the same from one photo to the next, his subjects and their words provide an extraordinary and insightful variety.

Fisk's project reminded me of a project I saw years ago in Los Angeles. It was produced by Ed Rusha, a fine artist and photographer. Rusha mounted a motor-driven camera to the front passenger window of his car, lens pointed outward, attached a cable release, and photographed other drivers throughout Los Angeles. The result was as literal an expression of L.A. street photography as you can imagine. It was also one of the best possible ways to approach street photography in Los Angeles, where drivers outnumber pedestrians ten to one. In a later project Rusha photographed every building on both sides of the famous Sunset Strip, in sequence, from one end to the other.

Anyone who has browsed the art photography section in a large bookstore can see similar examples: mothers and daughters, fathers and sons, sisters, the elderly, nudes with freckles... The list goes on.

If you want to come up with a simple idea of your own, look for something that has enough scope that you'll find plenty of subjects to photograph, yet not so much that your project lacks a clear and obvious focus. Also look for something that allows you to use the resources you already have at hand. Although it's nice to travel to distant lands and to use specialized equipment, it's certainly not necessary.

Most importantly, your project should be something you care deeply about or for which you have an intense interest. You'll need that energy to motivate you to keep at it from one day to the next, until you sense the project is done and you're ready to move on to something else. I promise you, you'll not only learn a lot about your subject, you'll learn even more about yourself.

Simplify

One of the challenges of street photography is to reduce the visual clutter and confusion you see all around you. You've got all types of people wearing all types of clothing, often crowded next to each other, surrounded by buildings, signs, billboards, utility poles, and more. Objects are in constant motion. Add color to the mix and the result is, more often than not, a visual mess. This is one of the main reasons why so many street photographers prefer to display their work in black and white: It takes color out of the equation, reduces visual distractions, and helps simplify the image.

That's fine if you're a fan of black and white and know how to avoid tonal mergers (a subject for a later discussion). If you prefer to shoot in color, there's another option, exemplified in the photo above. Instead of trying to simplify an image that has too many different elements competing for attention, try looking for compositions where the elements are already simplified. In the photo above, there are only three predominant colors: orange, blue, and black, with a touch of gray and brown. The shapes are large and bold. The patterns are simple and repetitive. These elements don't necessarily make this photo a masterpiece, but they do simplify the composition.

Here's another, slightly more complex example. The photo above has five colors: white, black, red, blue, and "flesh tone." (Yeah, I know. It doesn't match my flesh tone either. But can you think of a better name for it?) Although there's still a lot going on here, particularly with the spotted blouse and the map in the background with the dotted legend, it's a lot less than if dozens of competing colors had been in the frame.

These are by no means the only ways to simplify a composition. Other tools at your disposal include aperture setting for controlled depth-of-field, subject placement relative to the background, and focal length (wider vs. narrower). You're not obligated to use any of them--but if you do, your viewers will likely thank you for it.

 

 

 

Shooting In the Dark

Despite the bright lights from the neon, I wanted shadow detail, so I shot this handheld with a Pentax K-7, ISO 800, 1/10 second at f/2.8. This works out to approximately EV 3.5. Although the vibration reduction feature was on, this image is not perfectly sharp. The focus was on the lighthouse but should have been on the foreground. Still, it's not bad for handheld at 1/10 second and with a camera that's not reknowned for it's low-light abilities.

These days any reasonably alert person with an automatic camera can get a sharp, well-exposed photo outdoors in bright daylight. Take the same camera indoors under low light and things can get ugly. It will struggle to focus quickly and accurately, especially if it’s equipped with an f/3.5-5.6 zoom lens. Even if you do manage to focus you’ll discover that the limited maximum aperture forces you to use slow shutter speeds, high ISOs, or both, and even then subject motion can be a problem. Anyone who’s ever tried to photograph an active child indoors at night with normal room lighting knows exactly what I mean.

Those of you who own fast primes needn’t feel smug. True, you can use faster shutter speeds and/or lower ISOs, but fast apertures often result in narrower depth-of-field, increased aberrations, and reduced image contrast, not to mention the possibility of focus-shift. Perfect focus can be elusive at best.

And then there’s the issue of white balance. Mixed lighting is the norm in most interior spaces these days. You’ll find tungsten lights in some fixtures and fluorescent lights in others. Even the flourescent lights may have different color balances, with some being greenish, some yellow, and others more cyan. Shooting raw or attempting a custom white balance won’t necessarily solve this problem because correcting for one light source often exaggerates the effects of the other.

Here's a classic example of mixed lighting. I corrected the white balance for the sign in the foreground and the server's flesh tones and decided not to worry about the sickly yellow background. This was shot at ISO 800, 1/90 second at f/2.0, which is roughly EV 5.5. The guitar pick shaped highlights in the upper-right corner are the result of light entering the lens at an oblique angle.

Electronic flash can come to your rescue. It’s bright and its daylight balanced. Then again, direct flash can result in photos that have that “mug shot” lighting effect we know so well. If you’re lucky there will be a white or neutral-colored surface nearby that you can bounce the flash off of for softer, more indirect light. If you’re not, the walls will be green or magenta or some other color cast that’s hard to remove even if you’re shooting raw.

Tripods? They’re great if you don’t mind carrying one around, have the time and space to set it up, and you’re shooting a relatively stationary subject. On the other hand, if any one of these things isn’t true, your tripod is likely to stay at home, in the car, or in the studio—anywhere other than attached to your camera.

The situation isn’t quite as hopeless as it seems. In fact, if you can master the art of shooting in the dark, shooting in broad daylight becomes a breeze. Here are a few practical tips for improving your keeper-to-delete ratio.

1. Go for slow and steady.

You’re going to need to pay close attention to your technique and camera settings. Make sure your shutter speed is one at which you’re capable of holding your camera steady, with or without image stabilization. If there’s anything nearby that you can use to help brace your camera, by all means use it. You should also wait for your subject to be either at rest or at the peak of action. Maintain a relaxed state of alert preparedness, let the picture come to you, and you might be surprised what you can catch.

2. Observe the direction and quality of light.

Unless there's literally no light—in which case you’ll have to add your own—there’s a continuous light source somewhere that’s creating highlights and shadows that clearly visible to the naked eye. So take a good look at them. Are the highlights where you want them? Is the background free of bright areas that compete for attention with your subject? Remember that highlights are where most viewers will look first, so try to make them count for something, even if you have to move yourself, your subject, or the light source to do it.

3. Know your camera’s capabilities and limitations.

For example, a camera that focuses perfectly in bright daylight may back-focus when the light level drops to EV 4 or lower—unless you’re using a lens with a maximum aperture of f/2.8 or faster and use the center AF sensor, in which case everything is fine. Similarly, your camera may produce great ISO 1600 images when you shoot raw but look horrible if you shoot JPEGs. The best way to discover a camera’s limitations to push it to the edge—low light, dark subject, high ISO—until you discover the point at which it falls off. Back off from there and you’ll know the just how far you can go. By the way, I suggest you base “acceptability” on a print that’s as large as you’re likely to produce. For some this will be 4x6 inches. For others it will be 11x17. In either case, an image that looks horrible at 100% on your display can look surprisingly good in a print.

4. Use the fastest lens you’ve got.

Even if you have to sacrifice image-stabilization to do it, the faster aperture will give your camera a lot more light to work with than a kit zoom that maxes out at f/5.6. You may also see a substantial improvement in focusing accuracy: many cameras have higher-precision sensors in the center of the screen that produce more accurate results with lenses of f/2.8 or faster.

5. Try manual focusing.

You may discover that you can focus more reliably in low light than your camera’s AF system can. If your camera is mounted on a tripod and you’re using an intermediate aperture, you don’t even have to look through the viewfinder. You can use the distance scale on the focusing ring (assuming your lens has both), guesstimate, and let depth-of-field mask any slight inaccuracies.

6. Be willing to tolerate less than perfect results.

It's extremely difficult to capture low light photos that are perfectly in focus and have perfect white balance, high resolution from center to edge, and all the other attributes of technical perfection. You'll have a lot more fun if you aim instead for emotional perfection. Capture the mood. Let motion blur work to your advantage. Emphasize the often fantastic colors of artificial lights. Focus on the process instead of the goal and you may discover you've taken some fantastic photos.

You can thank me later.

What a Difference a Curve Makes

This is what you get when you photograph a relatively low contrast subject under low contrast lighting, which in this case was open shade on a cloudy fall morning. Not very inspiring is it? Still, it has potential.

It's no secret among faithful readers of Shutterfinger that when it comes to image manipulations in Photoshop and Lightroom, I fall firmly into the "less is more" camp. That's not to say I never manipulate my images. I do. I just try not to make it obvious. I try to do it in a way that enhances the subject without drawing undue attention to the enhancements themselves. (But that's just me. There are other equally valid approaches to photography and Photoshop. I've picked mine, you're free to pick yours.)

That said, it occurred to me this morning that providing you with a comparison between one of my originals and how it would look post-manipulation might be enlightening. Aside from some minor cropping, sharpening, and white balance adjustment, the only significant change I made was to apply a classic "right-tilted S"  contrast curve. This curve darkens the shadows, lightens the highlights, and increases separation in the mid-tones. The result is presented below.

This is the same photo as the one above, but with more "snap" and tone separation. Notice how colors and tones that weren't apparent in the first photo are easy to see in the second?

You may or may not care for the photo itself, but there's little doubt that the second is more eye-catching than the first. It also serves as a reminder that first impressions can be deceiving. The difference between a dull photo and one you'd mount on your wall may be only a few minor adjustments away. The first trick is to know which ones are worth a little extra effort and which aren't; the second is to know what type of adjustment. That's what makes good photography an art and, in my humble opinion, so much fun.

What to Improve Your Color Photography? Try Shooting Black & White.

Even though there's enough tonal contrast and graphic design to entertain the eye in this photo (scanned from color transparency film, by the way), compare it with the version below to see how it looks in color.

Back when I first got into photography I shot almost exclusively in black and white. Although color film was available (I'm not that old!), developing it was beyond my abilities or interests. Black and white film was relatively cheap, easy to develop and print, archival, and "artsy," so I stuck with it.

Among other things, that meant learning how to see in black and white; or, more accurately, how to interpret how a scene in color would translate into shades of gray. I quickly discovered that just because something had contrasting colors--red against green for example--didn't mean it would have contrasting tones when shot in black and white. In fact, reds and greens of similar reflectivity would often reproduce as the same shade of gray. That's why skilled B&W shooters carried color filters. A red filter would darken blues and greens while lightening reds and yellows. A green filter would do the opposite.

Filters aside, being successful at black and white photography requires developing an eye for the fundamentals of an image--its lines, forms, contrast, and gradations between highlight and shadow. Are these elements strong and dynamic, soft and flowing, or perhaps a combination between the two? Where do the lines and brighter areas lead the eye? Does it lead where you want it to? Does it create a sense of tension or resolution?

As cool as it is to see a pink Cadillac, I don't think this photo would be nearly as interesting without the contrast between the curves of the car and the straight lines of the concrete and metal structure. But that's just me. What do you think?

When you're visualizing in this way colors become secondary or in some cases superfluous. This can be a good thing if you're too often seduced by scenes simply because they're colorful. If you've got an image that's strong even without color, then color can become a bonus; that little bit extra that changes the comments you get from "Not bad," to "Wow!"

As for the actual how-to in all of this, here are three concrete suggestions:

1. Shoot black and white film. The lack of a review image might seem daunting at first, but you'll be surprised at how quickly you learn to pre-visualize in B&W when you don't have any choice.
2. Shoot JPEGs with your camera set to monochrome mode. Most DSLRs let you add color contrast filtration such as red, yellow, green, etc. Experiment to your heart's content, take note of the effect, and learn.
3. Shoot raw and temporarily convert your images to grayscale when sorting and reviewing them. You may find that the ones that stand out when rendered in shades of gray are just as strong if not stronger in color.

Choose whatever you find most attractive and disgregard the rest. But do try one of them. At the very least it will open your mind to new possibilities--and who knows? You might even discover that your images look better in black and white than in color.

Photographer At Play

I take a certain pride in the fact that this particular image looks just as good in black and white as it does in color. If you don't believe me, try it for yourself. (Just don't post it somewhere else as your work. That would be wrong.)

Last week I wrote about the stresses involved in doing a professional photo assignment. Today it's the opposite: The pleasures of shooting what, when and how I please.

What I please, at least for now, is what Philadelphians refer to as "Center City" -- the business, political and cultural hub, full of tall buildings, narrow alleyways, architectural wonders, ceaseless activity, and busy cosmopolitans who couldn't care less about me wondering around with a camera.

When I please is in the morning or afternoon, when the shadows have a more rakish angle and the streets aren't so busy that cars and pedestrians become more of an obstacle than interesting elements in a photograph. That said, it's rare that I'm in the city for the sole purpose of taking pictures. I'm there for a business meeting, or to take my kids to an event, or for a rare dinner date with my wife. My camera is definitely not the star of the show, so I value having one that's small and lightweight yet capable of producing pro-quality results. The Pentax K-7 I've been using fits the bill nicely. I can mount either a 21mm f/3.2 Takumar or 35mm f/2.8 Macro-Takumar, carry it in a messenger bag or briefcase, and be good-to-go for practically anything I care to shoot.

In some ways this is the same picture as the one above, only different. One thing is definitely the same: the camera, lens, lighting and technique. Does this help give my work a more coherent look? I hope so.

What I shoot is typified by the two images I included in this post. I love images that combine strong graphic elements, bold contrast, visual tension, and the occasional human being wandering through the midst of it all.

Images like this are trickier to capture than they might appear. Deep, dark shadows often fool automatic exposure meters into overexposing the screen. That's where the "how" I shoot comes in: I eliminate exposure problems by shooting with the camera set to manual. As experienced photographers know, a bright sunny day in a city requires pretty much the same exposure all over the world, 1/500 second at f/8 at ISO 100. I might adjust a bit on one side or the other, but once the exposure is locked down I never have to worry about it varying from one shot to the next, no matter how I reframe the image.

Sometimes, when I'm feeling particularly confident or I'm low on card space, I'll shoot JPEG-only. Long-time readers of this blog know that I'm not the type of photographer who will tweak every single image I shoot just because I can. The less unnecessary time I have to spend at the computer, the happier I am. And in the end, isn't the freedom to do it your way really what it's all about?

What's the Most Valuable Thing to Learn?

It's that time of year. Even though I'm a street photographer at heart, even I can't help but be moved by the crispness in the air and the colors of fall. That's what I wanted to express in this photograph. In this case, capturing it was more a matter of composition than technique.

I recently had a friend mention that she had bought a digital camera and wanted to learn how to use it. It was a point-and-shoot, so I asked what she meant by "how to use it." Its operation didn't seem particularly complicated. She replied that she wanted to learn how to use it to take pictures that were better than just snapshots. It was her impression that this required a more intimate knowledge of how to use a camera than she possessed. She wondered what suggestions I had to help her.

I have to admit I was stumped. It's not as if I know nothing about photography. The problem was where to begin. Should I explain apertures, shutter speeds and ISOs? Do I explain focal length, angle of view and depth-of-field? Would understanding all of this really improve her abilities? As important as technical knowledge may be, it's only a means to an end, and not necessarily the only means either.

On a whim, I tried a metaphor: "It's sort of like learning to play an instrument," I said. "The learning gets a lot easier when you know what style of music you're trying to play. If you're familiar with the style then you can concentrate one learning the technique it takes to play it."

This idea seemed to make sense to her, but whether it will help her improve her photography neither of can say for now. Knowledge, even if useful, still has to be applied. Still, it seems to me that the most important way to improve your skill as a photographer is to have some sense of what you're trying to achieve or say; a sense, even if vague, of how you'd like a picture to look and how to get your camera to produce what you want. Without this you're basically just snapping the shutter and hoping for the best.

So that's what I consider the most valuable thing to learn. What about you? What, other than this incredibly thought-provoking blog*, has been the most important factor in your own growth as a photographer? What's the most valuable tip you would pass on to a friend of yours who wants to get better?

*I'm being ironic and self-deprecating here.

A Follow-up To Focusing Foibles

It occurred to me that after going on at length about the challenges of focusing with wide aperture primes on APS-size DSLRs I should provide a few visual examples of what I'm talking about. If this proves to be of any interest to you then I'd encourage you not to simply take my word for it. Try doing a similar test for yourself to see if your results are like mine. Whatever the result, you'll learn something about how your fast lenses perform and how to interpret what you see through your camera's viewfinder.

The photo above shows what happened when I focused my Canon 50mm f/1.4EF at the 10cm mark on this ruler. I shot at maximum aperture. The ruler was held in place by a clamp on a light stand and was parallel to the floor. My camera was on a tripod, pointed downward at a 45 degree angle.

Two things are evident: First, the point of sharpest focus is a bit closer than 10cm. I'd estimate it at roughly 9.5cm. Given that the actual focus point may have been slightly different than what's indicated in the viewfinder, this isn't bad.

The second thing you notice is that the out-of-focus area in the background has a green tinge while the foreground has a magenta tinge. That, my friends, is chromatic aberration in action. It would be harder to see with a multi-colored, textured subject but on a subject like this it's hard to miss.

This second photo shows what happens when I stop down to f/5.6. As you would expect, the greater depth-of-field renders the 10mm mark more than acceptably sharp. But also notice that the overall zone of focus has shifted back, away from the camera. That's focus shift. As for the chromatic aberration effect, it's still evident but less obvious. Once again, keep in mind that I intentionally shot this subject this way so that you could see both effects. The 50mm f/1.4 EF is one of Canon's best lenses, so it would be a mistake to interpret these results as "defects."

The bigger point I'd like to make--one that I realized only after comparing the photos to what I saw in my EOS 30D's viewfinder--is that even though I was focusing the lens at maximum aperture, the way most people do, the image I saw through the viewfinder looked more like the image shot at f/5.6. In other words, I saw four more stops of depth-of-field than there actually was.

No wonder it's so hard to manually focus a DSLR with a standard autofocus screen! The reduced magnification with APS-sized DSLRs only adds to this handicap. As for the so-called depth-of-field preview button, my experience is that all it does is darken the viewfinder. What you see through the viewfinder is seldom even close to what you get. I can't speak for all DSLRs, but of the ones I've used, the rear LCD gives you a much better idea of what the actual image will look like than the optical viewfinder.

Make of this what you will. My personal conclusion is that when a particular depth-of-field and pinpoint focus are necessary you'd be wise not to take what you see in your viewfinder too literally. When possible, bracket your apertures and your point of focus. Since one of the advantages of digital shooting is that there's no incremental cost to shooting more pictures you might as well take full advantage of it.

As for all of you Luddites out there who are still shooting film cameras with manual focus lenses and manual focusing systems, you wipe that smug smile off your face right this minute!

Addendum: I don't want to give the impression that I'm singling out APS DSLRs for criticism based on their viewfinders. The same criticism could just as easily be directed at 35mm rangefinders or twin-lens reflexes. In both cases, what you see is not what you get. The one difference with APS DSLRs though, is that you're more likely to assume their viewfinders work exactly the same as with 35mm SLRs. They don't. In some cases it's not even close. So if you really need to check for depth-of-field or the lack of it, check the LCD, not the viewfinder.