Walking The Knife's Edge Of Shallow Depth Of Field

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Here are the three really critical lenses to own if you want to achieve really crisp images wide-open. Zooms won't cut it, so fast primes are the way to go. Clockwise from top left: Canon's 135mm f/2 L, Canon's 85mm f/1.2 L, and Canon's 90mm f/2.8 TS-E Tilt-Shift lens.

Recently I've begun to look at things differently. As a working commercial photographer, much of my work consists of really tack-sharp images. While I've always worked with foreground and background areas that may be out of focus, the "look" has always been "sharp."

Changes in the style of editorial and commercial images over the past seven or eight years have changed the way I approach many assignments today. We've all seen the narrow depth of field product photography popularized by lifestyle magazines like Martha Stewart's Living, where the photographer holds just enough depth to get the front of the object in focus, then everything else falls out of focus quite rapidly. In the mid-1990s the shifted focus plane was all the rage. Using either a view camera or a funky lens mount like the wild Zorkendorfer, creative photographers found that by swinging their film planes in the "wrong" direction, they could get some deliciously soft and creamy out of focus areas. I find that I'm getting more and more calls from clients looking for the really short depth of field look, so it was time for me to really figure out how to create this effect reliably.

These shots of pro model Lauren Michelle show just how dynamic this look can be. A close look at these images show that only one eyelash is really sharp--everything else gets soft and dreamy without the flat "out of focus" look that slower lenses produce.
Photos © 2004, Jay Abend, All Rights Reserved

The Wide-Open Dilemma
It should be obvious to any seasoned photographer that most lenses perform their worst when they are wide-open. In general, the really sharp "sweet spot" for most lenses, even the most expensive prime lenses, is in the middle of the aperture range, around f/5.6-f/11 for most of us. It is also true that as you stop down toward the lens' smallest aperture, your depth of field increases dramatically but the lens will also soften up a bit. Sure, sometimes these rules don't hold fast, since some very inexpensive zoom lenses perform fairly well wide-open, but in general you'll find that wide-open can be a dangerous place.

Famous Fast Optics
In the world of shallow depth of field photography there are a handful of lenses that are legendary. For example, Leica-M owners speak reverently of the 50mm f/1.0 Noctilux. Additionally, I've created some amazing images with a Nikkor 55mm f/1.2 on a Nikon F2, and made some nice available light portraits with a Canon 85mm f/1.5 on a Canon rangefinder body back in the '80s. In modern glass few lenses can match the Canon 85mm f/1.2 for sheer "buzz." Wherever you go, fashion and portrait photographers are talking about this lens, or Nikon's equally desirable 85mm f/1.4 Nikkor. Other hot glass for the wide-open look? Several manufacturers make a 135mm f/2 lens, and the classic sports lens, the 300mm f/2.8 is also a champ for headshots with blown-out backgrounds.

I like this look for portraits. Here Lauren Michelle sat on some stairs and I got at least 10 ft above her. Tightly cropped with a 135mm f/2 wide-open, only her face is sharp--from the neck down it blows out quite nicely.

Besides shallow depth of field, artificially throwing parts of the focal plane out of focus can also make for some dramatic images. The two leaders for this kind of photography are Nikon's 85mm f/2.8 Micro-Nikkor and Canon's 90mm f/2.8 TS-E. Both lenses are engineering marvels, allowing full automatic operation (though manual focus only) with provisions for lens shift and lens tilt. By rocking the lens fully to one side and shooting wide-open, you can get a full-length body shot with only about a 12" slice of critical focus. Everything else is soft and blown out, but with the dreamy, creamy "soft lens" look that no Photoshop filter can recreate.

Unfortunately, when it comes to the hottest looks with the hottest lenses there is no cheap way out, though I have found that a simple 50mm f/1.4 lens can do a fabulous job as well. I own a 50mm f/1.4 EF lens for my EOS-1Ds digital camera, but probably break it out about once every two years. That's a big mistake, since I've noticed that this lens produces some of the nicest images of any lens I own. Even brand-new 50mm f/1.4 lenses for any camera system are hardly bank-breakers, so if you only shoot with a medium aperture zoom now, do yourself a favor and get one good normal lens.

Wow, I love the tilt-shift lenses! Nothing compares to this look. I swung the lens way out to only get a small slice of focus, but as you can see both her face and the building (approximately 100 yards away) are sharp--cool!

The Manual/Autofocus Difference
When shooting wide-open you remove the typical safety net favored by many autofocus shooters. Unlike focusing by eye, your autofocus camera racks the lens until the contrast in the critical points of the image are at a peak level, then it stops. According to where your lens was focused before the shot, you'll either have focus at the front or back of your subject--rarely in the center. When you focus by hand you tend to rack through the focus points, using your brain to average out the focus points and give yourself a bit of depth. Even wide-open the difference between manual and autofocus can be startling. No lens exacerbates this problem more than Canon's 85mm f/1.2. This big, heavy lens has a fairly slow autofocus system, since those big heavy elements take a while to get moving. This lens should definitely be focused manually.

I also like to bracket all of my wide-open shots. Not bracketing for exposure, as is the custom, but bracketing for depth. In other words, I manually focus right at the front of the subject, then fire off a half dozen shots, slowly rotating the focus ring through the zone from front to back. This works great on product shots, but for people there are those times when the right expression doesn't match the correct focus point.

Here's a look that I've been getting with a 4x5 view camera for years, with the back swung out to really limit the depth of field. While this high-end Canon 90mm f/2.8 TS-E is a wonder, I've also received decent results with a cheap Russian tilt-shift on a Nikon body.

Exposure Considerations
One of the problems with shooting this style is exposure. While most of us fight for light, trying to get a fast shutter speed and decent aperture combination, shooting with your lens at f/1.2 creates an entirely new set of problems. With a typical SLR camera at ISO 100 an f/stop of 1.2 in broad daylight results in a shutter speed of 1/4000-1/8000 sec. Unless you own a high-end SLR you're likely limited to 1/1000, 1/2000, or 1/4000 sec. Did you ever think that 1/4000 sec would be too slow? Of course slower film or forcing your digital SLR into a custom function, low ISO mode are solutions to this problem, but keep in mind that sometimes too much light will be an issue.

A Digital Alternative?
There's a lot of talk about using electronic means to create this effect. Sure, I've used the Gaussian Blur filter in Photoshop over the years, as well as Andromeda's excellent "VariFocus" plug-in. Photoshop CS now has a very effective "Lens Blur" tool, which does a good job of recreating this effect. None of them, however, really touch the look of a real wide-open or swung lens. Even if you could do a terrific job of carefully silhouetting your foreground subject, in my opinion you'll never really duplicate the look that you can simply create optically with the right lens.

You don't need expensive glass to get similar effects. For this publicity shot of psychologist and author Edward Klein, I used a plain-old 50mm f/1.4 lens on a Canon EOS-1D set to ISO 400. Even though we were in a busy and cluttered restaurant, a simple window and a white card for bounce reflection took care of the lighting. Handheld at f/1.4 at 1/60 sec, I got a lot of very crisp, usable images.

The Fuzzy Part
The really cool part of this kind of photography is the fuzzy stuff. Landscape photographers refer to the out of focus background as "bokeh." Outdoor shooters argue about the lenses with the nicest bokeh. How can one lens be prettier out of focus than in focus? Well, a lot of it has to do with the optical design, and a lot has to do with the iris of the lens. Some cheapo lenses use a crude eight-blade iris, which creates coarse, octagonal-shaped highlights and very low contrast out of focus areas. The expensive lenses often use 22-blade curved leaf iris units--for nearly perfect circles at all apertures. Add that to the precision coatings and asphercial lens elements in the better lenses, and you can see how they outperform cheaper lenses. Who's got the prettiest bokeh in the world? In my opinion it's a tie between Canon's 85mm f/1.2 L and their gorgeous 200mm f/1.8 L. Neither is cheap but both are great.

Dealing with this narrow depth of field can make for some very exciting photographs, and some very disappointing photo shoots. Even experienced pros can come back with hundreds of unusable images (take it from me). You can always play "safety" and shoot a bunch at f/4 just to ensure that you have something worthwhile, but I find the methodical manual focusing, painstaking focus bracketing, and patience can really do the trick.

Try it out. If you have the right kind of camera and lenses, I think you'll be impressed at how different your images look when shot to intentionally limit the depth of field.

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