When To Turn Off The Focus
Sometimes The Eye Is Quicker Than The Lens

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Shot with a 600mm lens, autofocus has plenty of detail to grab and keep the car in sharp focus while it was being pushed into the pit area.
Photos © 1999, Jay Abend, All Rights Reserved

One of the most important tips that I give aspiring photographers who own modern 35mm cameras is to learn to use their cameras totally manually. That's right, turn off the autoexposure and the autofocus, set the motor drive to single frame, and use your eyes and your brain instead.

Don't get me wrong, I'm not one of these Luddites harking back to the grand old days of Ikonta Bs and selenium cell light meters. I'm paid to deliver a consistently great image to a client and I'll use whatever tools are available. I own one manual focus 35mm system and one autofocus 35mm system. I tend to use both systems in roughly the same manner. I prefer to meter things with a handheld incident meter where applicable, and I like to focus for myself. That doesn't mean that I take my own advice. I tend to leave my cameras in the autofocus mode with Program exposure set so I can grab them and fire off a few frames and expect decent exposure and focus without a second thought. Since I once took some pretty nice pictures with Nikon Fs and F-2s before auto-everything existed, it just didn't dawn on me that I needed a camera that could focus for me.

Shooting wide open with a 200mm f/1.8 lens, the five zone focusing system in the camera grabbed the leaves on the top of the frame to focus on, leaving the child's face a bit soft. Manual focus would have helped out.

When I first saw a press photographer using a Canon EOS-1 with a 28-70mm f/2.8 autofocus lens I was just blown away. I borrowed the camera for a minute and was dazzled by the focusing speed and accuracy. Here was a tool that I really needed, I thought; so I sold off a flight case full of Nikon F2s and F3s, Nikkor glass and related accessories and bought the EOS program lock stock and barrel. I must admit that the ergonomics of the EOS-1 and now the EOS-1N are truly wonderful, and I really have learned to love this system, but I have relied on the autofocus and autoexposure much less than I thought.

The press photographer who let me fondle his camera can really use as many auto features as he can get, since in many cases press guys must shoot well before they are comfortable with their exposure, focus and framing. They bang away as best they can and rely on a combination of determination, experience, talent and luck to get the image they need. In cases where there is enough time to get the image, there are still the issues of access to the site or subject, camera position and the difficult to define "decisive moment" that makes routine documentary photography inspirational. In the few instances where I have been thrown in with the press guys, they've eaten me alive and got the great shot while I was still jockeying for position. If I'm one of those guys, I want a camera that can help me--even occasionally think for me. I've had a chance to play with an early Nikon F5 and I am sure that this remarkable camera will win over a lot of press guys who have jumped, like me, to EOS.

When shooting details of clothing for a catalog, autofocus was perfect. As the models moved around the set, focus stayed spot on and I could concentrate on the clothing and the client's needs.

Once I had owned my EOS gear for a while and the newness of the system wore off, I took a good hard look at page after page of transparencies that I had shot and realized something very important: my work was no sharper on average than that shot with my manual focus Nikon stuff. In fact I found a few instances where the work was consistently out of focus, with a few in focus shots. Did the autofocus malfunction? Was this technology over-hyped? Of course not. The problem was that autofocus is dumb technology. Now, the engineers who invented it are probably quite brilliant, but the resulting product is just plain dumb. Aim it at the wall and it will focus at the wall, even if you want some tiny detail in the foreground in focus. Newer multizone focusing systems and Canon's great eye control focus are big improvements over the center-only focus schemes of old, but there are still hundreds of stuations where I feel that it is faster, easier and safer to focus manually. In complex situations, figuring out a way to tell the camera what to focus on may actually be more time consuming and more difficult than grabbing the focus ring and doing it yourself.

I tend to use 35mm mostly for location work, especially for musical product manufacturers who often assign me to shoot rock stars in concert. Even the best autofocus system tends to get confused by the extreme contrast between the performer and the black of the background, as well as the colored lights that often hang from lighting rigs overhead. In some cases the ambient light levels are quite low and the autofocus tends to hunt back and forth; in other cases the autofocus locks in on the instrument when I want the face in focus, or vice versa. I moved to autofocus especially to help me in these difficult situations, but I soon learned that the best way to focus was with my own eyes. I ditched the EOS standard matte screen and installed split image rangefinder screens like my Nikons used to have. Since then my focus looks better and my work looks sharper. In situations where the performers are very well lit, especially on film sets during video shoots, I leave the autofocus on because I find the autofocus is better at continually refining the focus as the performer moves around. Since I am usually shooting wide open, focus has to be spot on, and the camera seems to do a better job than I can in those circumstances. When I'm trying to capture two or three performers at once I always shut the autofocus off so I can pick my focus point or even continually shift the focus point as I shoot.

From this camera position I only had about 1/2 sec to shoot each car as it came around. With autofocus on the camera couldn't catch up. By manually presetting the focus I could grab three frames every time the car came by.

Oddly enough, I love autofocus in the studio. You would think that one of the places where you really wouldn't need autofocus is in a totally controlled environment, but I've found that when I shoot 35mm in the studio, whether for products or people, I like to move the camera around and constantly change perspectives. In the old days that meant continually rocking the focusing ring back and forth trying to maintain constant focus. Since those days I've discovered the EOS Custom Function 4 secret. (CF4 assigns the autofocus function a button on the rear of the camera or on the motor drive booster. The camera focuses only when you press the button rather than the shutter release.) I can't live without autofocus in the studio. As I move around I keep hitting the focus button on the camera until I get a focus right and also until it "looks" sharp to me, then I lay off the focus until I or my subject moves. This allows me to focus on something in the foreground by tipping down the camera, centering the object and automatically setting my focus. I then leave the focus locked on the foreground and re-frame the shot, and shoot knowing that the camera will not re-focus until I tell it to. The dumb technology now borrows a little smarts from me and we're working as a team. I find this preferable to the "press the shutter halfway" focus lock technique, which must be repeated before every shot or the camera simply re-focuses on the scene as it sees it, which may be on the wrong object.

There have been hundreds of occasions where I have switched off the autofocus, many of which surprised even me! On assignment at the Daytona 500 I found that the "hunting" time of my long lenses was cramping my style as the cars came around to my camera position. I could cut down on the hunting time by presetting minimum and maximum focus distances on the Canon 600 f/4 I was using but it still just seemed faster to me to manually follow the cars. I found the opposite was true when photographing the cars coming toward me. I've always had trouble obtaining the right focus point when subjects are coming toward me, and my chromes sure proved that I was routinely blowing it. When setup to shoot the cars three-wide coming around turn four at Daytona, I was shooting with the 600mm f/4 and a 1.4 teleconverter for an effective 840mm f/5.6. This gave me almost no depth of field to speak of. Focus was either spot on or I was fuzzy. You would think that objects coming toward you would be easier to focus on than objects speeding perpendicular to your position, but I have found that I continually misjudge correct focus. With the autofocus on every single shot was spot on. Very impressive.

The man climbing on the car to the left and the press photographer with the yellow hat trying to get in front of my lens might have fooled the autofocus, but since I was focusing manually I stayed sharp on the race winner.

A lot of parents have the same problem shooting their kids playing sports. Shoot a wide shot of the field at infinity and everything's fine. Rack your lens out to 200mm to catch your kid making a great play at second base and you're ready to shoot before the lens has motored its way into focus. I thought the speed and accuracy of autofocus would be a big help in such a situation, but I can focus from 6' to infinity in a fraction of the time that the camera can. Pros know all about this lag, both in camera reaction time and human reaction time, and keep a small armada of cameras ready and choose different camera/lens combinations to focus on different parts of the field. A wire service like Associated Press will send a small platoon of photographers to an NFL game, each person responsible for a different athlete or part of the field. You can't cover everything, so you increase your batting average by trying to anticipate action before it happens and have your camera and lens pointed in the right direction, focused and ready to go. This way if the play comes your way you've got the perfect shot. If it doesn't, wait until next time.

The best and most impressive use of autofocus is the ability to hand the camera to a total amateur and have some well-focused shots come back. I often leave an EOS-1 body with 28-70mm lens and Canon flash laying around the house for my wife to use to photograph the kids. While this is a pretty formidable piece of pro gear, when set to the "P" Program mode anyone can crank out roll after roll of fine looking shots. If I were making gigantic enlargements of these family snaps I would surely notice that in many instances the camera is shooting at f/2.8 and has chosen to focus on something just in front of or behind the intended subject. The focus isn't off by much, but it is off. The 4x6" prints look just wonderful, but if this work was intended for publication it wouldn't cut it. Since most nonphotographers have a difficult time discerning accurate focus through the lens of an SLR, autofocus is a substantial improvement.

One instance where I routinely shut off the autofocus is when shooting with a very wide angle lens. Since SLR autofocus systems look for contrasting horizontal and vertical lines, the more these converging lines and patterns "pop," the faster and more secure the focus. Very wide angle lenses have extremely wide depth of field, so the objects tend to appear almost sharp even when the focus is off. When shooting at normal distances, a typical 18mm f/3.5 lens tends to appear very sharp to the camera. I have found that, when using a really wide angle lens up close, focus is accurate, but for scenics and the like the camera doesn't seem to "see" the foreground objects as clearly and the camera will routinely hunt back and forth looking for focus.

The one problem with using modem autofocus cameras and lenses manually is the lack of a good old-fashioned focusing ring. In the old days the smooth, well-damped motion of the focusing ring was a measure of the quality of a lens. Today, most optically fine lenses have thin polycarbonate focusing rings that have very little damping. The result is it's quite difficult to dial in the proper focus and keep it there, since the lightweight focus rings are difficult to keep still. The rare examples are some of the pro caliber lenses, especially the big pro glass like 300mm f/2.8 and 70-210mm f/2.8 lenses. My Canon 300mm f/2.8 has a wonderful damped focusing ring, perhaps as smooth as my old manual Nikkor 300 f/2.8 ED. Even some reasonably priced pro glass can be quite smooth. I have a few Sigma and Tokina pro lenses and their focusing rings are wide and quite nicely damped. My consumer lenses from the same manufacturer seem to be a bit lighter and the focusing is very "breezy," not as well damped as I would prefer. My Canon 35-350mm lens has a nice focusing action, but it is a substantial and heavy lens that just wears me out when hand holding for a long period of time. I have become quite attached to the new version of the Tamron 28-200 zoom, but I've found the tiny non-rubberized focusing ring to be a little difficult to manage. I love the lens anyway and make the best of it.

Users of cameras that support older manual focus lenses have it easier. You can still use your old heavy-duty lenses and focus yourself. With my EOS system I'm limited to EOS only lenses. Of particular interest to me is the Contax AX, which supports the excellent Carl Zeiss lenses for Contax manual focus cameras and moves the camera back, rather than the lens, to focus. For really long lenses you need to set the approximate focus, and in the samples I've used you can use the focusing ring yourself to assist the autofocus. I like this system a lot but I can't switch camera systems every time something exciting comes along, or I would have switched between Canon, Nikon and Leica about five times already.

The key ingredient in any kind of art form is to understand your medium well enough to use it to your advantage and create work that fulfills your vision. Since my art form usually means painfully sharp images, I need to know when to let the technology do its stuff and when to do it myself. By understanding when the camera is best suited to choose the focus for me I can relax and rely on the autofocus to do its job. In those circumstances where I know that I've had some focus problems in the past, then I'm in the driver's seat. In the constant search for maximum image fidelity, consistent focus is of paramount importance. The next time you're out shooting for yourself or on assignment, try comparing a roll shot with autofocus "on" and one "off." See for yourself which approach yields maximum sharpness or adopt a combination of the two. I think you'll find that each approach has a slight advantage in certain circumstances, but find out for yourself!

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