by John & Barbara Gerlach

I have used Canon EOS cameras for nearly two decades while Barbara has used Nikon cameras for the same period. We shoot different cameras systems because each system has some advantages over the other in certain situations so we use the camera that is best suited for the situation. Also, nearly all of our workshop and tour clients are shooting one of the two systems so it is easy for us to help them since we own both systems. Since cameras are complicated and instruction manuals are packed with detailed information which doesn’t always make the most interesting reading, it’s helpful to avoid switching from one system to another. Digital photography is here to stay and the clear leaders in digital cameras are Nikon and Canon. Both are excellent systems. I prefer Canon while Barbara wouldn’t part with her Nikons. So if you ask either one of us which system to get, you would get two different answers. You can’t go wrong with either.

The huge advantage of picking a system and staying with it is once you have learned how to use a Canon EOS or Nikon digital camera for example, other cameras in the line have many similarities. We shoot the most full featured models available in each system which currently is the Nikon D2X and the Canon EOS 1Ds Mark II. We learn both cameras as well as we possibly can. When the successor to either of these bodies comes out, we’ll get it right away and already know 80% of the instruction book so our learning curve to mastering the next generation of cameras is actually quite low.

We do study the instruction book very carefully, looking for any new capabilities that can help us take the images we want. I approach the manual like I was studying for a college physics test. I pick a chapter and study that hard which includes using a yellow highlighter to mark new important information. I even write short quiz questions down to see if I can remember the answers a few days later. I push all the buttons and go through the menus to make sure I can find my way around. Often with a new camera, I start with an easy chapter and try to master that. For example, prior to going to Kenya in 2005, I bought the Canon EOS 20D as a backup to my Canon EOS 1Ds Mark II. I started with the introduction and then studied Chapter 1 which was about getting started. Then I jumped to Chapter 4 which explained setting the AF, Metering, and Drive Modes. These are all easy topics to me that I knew I could master quite quickly and become more comfortable with my new camera.

Even a topic like autofocus though isn’t as easy as you might think. From teaching more than 150 people in week-long field workshops during 2005, it’s clear most students are not taking full advantage of their autofocus controls. Since I shoot Canon, I will discuss Canon controls, but Nikon can do most and sometimes more than Canon, though they may use different terms. The Canon EOS 20D has three autofocusing modes called One Shot, AI Focus, and AI Servo. To use these features, set the focus mode switch on the lens to AF. When the camera is set to the One Shot mode, point the middle AF point in the viewfinder to the place where you want to achieve perfect focus, hold the shutter button down halfway, recompose, and then press the shutter all the way to take the picture. It sounds like it is a fool proof way to accurately focus any subject that isn’t moving and it does work quite well if you are hand-holding the camera, something that I seldom do. This system doesn’t work well on a tripod because you don’t want to touch the camera or the tripod during the exposure to avoid causing the camera to vibrate which reduces image sharpness. Our workshop participants are generally greatly concerned about image quality so they use a cable release or a self-timer to trip the camera and run into serious out-of-focus problems. Here’s what is happening. Let’s pretend we are photographing some frosted blackberry leaves during the autumn. While working on a tripod, our clients would point the center AF point at a particular frosted leaf where they want to hit sharp focus and then recompose. Now the AF focus point is pointed between the leaves at a background several feet behind the frosted leaves. Pushing the shutter button to activate the self-timer or using a Canon Remote Switch RS-80N3 to take the image activates the autofocus so the camera focuses on the background instead of the leaves causing the leaves to be severely out-of-focus. One way to solve this problem is to turn the AF switch on the lens off immediately prior to taking the image. Of course you’ll need to turn it back on each time you want to take a new photo. With Nikon cameras, you’ll most likely have to turn the AF switch on the camera body to off. There is a much better answer that I will get to at the end of this article.

It’s usually best to sharply focus action by using continuous autofocus which is called AI Servo by Canon. By holding the middle autofocus point on the head or neck of a flying Canada Goose, the camera will continuously track the goose, adjusting the focusing for the changing distance to produce sharp images if the shutter speed is set high enough such as 1/1000 second. This works quite well and makes sharply focused action images much easier to obtain than in past years with manual focus lenses.

Recently, Canon has introduced a third autofocus mode called AI Focus where the camera acts like the One-Shot AF mode, but if the subject begins to move, it switches over to AI Servo AF. This sounds great, but I haven’t tried to use it yet so I just don’t know how well it works.

We have lead photo tours to Kenya for more than two decades. It’s terrific for wildlife photography. Most of the time One-Shot AF works great for a giraffe staring at you or a lion perched on a termite mound. But, if that giraffe or lion suddenly begins to move, it’s necessary to switch over to AI Servo AF. To do this with the Canon 20D, you need to press the AF button on the top of the camera, rotate the main control dial to select AI Servo AF, and tap the shutter button so you can begin shooting again. It doesn’t take long to do this, but it does make it impossible to instantly go to action shooting. Once again there is a better option for going from One-Shot AF to AI Servo AF and back again that most cameras can do, but the details are difficult to dig out of your instruction book.

Here’s how we handle autofocus for both the Nikon and Canon system. Most modern cameras have a way to separate autofocus from the shutter button. With my Canon EOS 1Ds Mark II and EOS 20D, I go to custom function #4 and set it on selection #1. This transfers autofocus to the AE lock button on the back of each camera. Pointing the middle autofocus point at the spot where you want the sharpest focus and pressing the AE lock button activates autofocus. Let up on the button and the camera will not refocus. In the case of many Nikon bodies, the camera already has a button on the back of the camera body that activates autofocus. We know this is true on the Nikon D50, D70, and D2x bodies. But, to get the autofocus off the shutter button, you have to go into the menu and turn if off. Now autofocus is only initiated by the back button.

At first it may seem cumbersome to activate autofocus on the back of the camera, but you get used to it in time. Using the back button to initiate autofocus solves a huge problem for photographers who shoot on tripods. No longer does the cable release or pushing the shutter button to begin the self-timer cause the camera to refocus on the wrong spot. You can leave the AF switch on a Canon lens or Nikon camera body set to the on position all of the time. Another huge advantage to putting the autofocus on the back button is you can have instant One-Shot AF or AI Servo AF whenever you want it without the need to look at your camera to change the autofocus mode.

Both of us use the following method with our Canon and Nikon bodies whenever photographing wildlife that could be still or moving at any given moment. We set the autofocus control on the button on the rear of the camera and set it for continuos autofocus which Canon calls AI Servo AF and Nikon calls it continuous-servo autofocus. We do not use One-Shot AF for wildlife because we don’t need to. Let me explain with an example. I was photographing a spotted hyena taking a bath in a large mud puddle. It was quietly looking at me as it sat half submerged in the puddle. I pointed the middle autofocus point at it’s face, pushed the rear AF button control and let up on the button when I had achieved focus. Then I recomposed and shot a few images by pressing the shutter button. Even though the camera was set on continuous autofocus (AI Servo AF in my case), the camera acted liked I had it set on One-Shot AF. As long as the distance from the camera to the hyenas face didn’t change, I didn’t have to refocus. If the hyena changed this distance, I performed the autofocus procedure just described again. With practice, it only takes a second to do. Eventually, another hyena ran past the first so I held the back button down to initiate instant continuous autofocus, panned with the hyena, and made a decent image of it running. If I had to go to the buttons and dials to change from One-Shot AF to AI Servo AF, I could have never made the image. By setting the camera up to continuous autofocus on the back button, I have a choice of One-Shot AF or continuous instantly. It’s a method that has worked well for us for many years now.

It doesn’t mean that we always have the camera set to continuous autofocus on the back button. There are times where we prefer the shutter button to initiate continuous autofocus. During our 2005 safari, I spent quite a bit of time with the folks in my safari vehicle who wanted to photograph flamingos in flight at Lake Nakuru. So one afternoon I took this group to a point of land that sticks out into Lake Nakuru where it’s likely that many flamingos will fly by the point closely so we could fill the frame. Since we were only doing action shots and knew we would not need One-Shot AF, I turned off custom function #4 so the shutter button initiated continuous autofocus. Since using the back button does require two fingers, one to hold the button in and the other to trip the shutter, it is a bit easier if only one finger is needed to begin the autofocusing and trip the shutter. We always proceed this way if we know we are definitely photographing only action.

On the other hand, during fall color we normally photograph subjects that aren’t likely to move such as mushrooms, colorful leaves on the trees, frost, and gorgeous landscapes. In this case, we set the camera autofocus control on the rear button, but leave it on One-Shot AF. We also set our camera to mirror lock-up because the movement of the mirror just prior to the exposure can jar the camera a tiny bit causing a slight loss of sharpness, especially at shutter speeds in the 1/8 to 1/30 second range. With my EOS 1Ds Mark II, I set the drive to a two-second delay. When I press the shutter button, the mirror moves up out of the way immediately, the camera counts off two seconds, and then takes the image. The two second delay allows any vibration produced by the movement of the mirror to dissipate before the actual image is taken.

We see a lot of Canon EOS 20D cameras in our workshops and they want to use the self-timer too. Unfortunately, they don’t have a two second choice on the drive button. When using the self-timer, they have to wait 10 seconds for the camera to finally take the image which seems like eternity when plenty of great subjects are begging to be photographed. If you have this camera and don’t like the 10-second delay, there is a trick to shorten the time to two seconds. Go to the bottom of page 88. In the small print you’ll find out if you set the mirror-lockup to on by going to Custom Function #12 and setting it to choice #1 (Enable), the self-timer will switch from a 10-second delay to only two seconds! This is another great feature that you really have to dig for in your manual to find out about. Remember that both the mirror-lockup and the self-timer feature must be turned on for this to work with the Canon 20D.

Most of the time when photographing static objects that won’t blow in the wind, I use the 2-second delay with self-timer on to get the best quality instead of using a cable release. There are times when tripping the shutter with the cable release is better though rather than using the two second delay. If you are photographing anything that can sway in a breeze and you have to wait for a lull, the cable release is much better because you can trip the shutter as soon as the subject holds perfectly still. With the self-timer, even if it is only two seconds, there is no way you can know if the subject will be vibrating in a breeze or not two seconds later.

By the way, we use the middle focus spot nearly all of the time even though most cameras permit selecting a number of focusing spots. What many photographers don’t realize is not all focusing spots are equal in terms of accuracy. Unless the lens is a fast f/2.8 lens, most focusing spots are only horizontal line sensitive while the middle sensor is both vertical and horizontal line sensitive. Vertical line detection is twice as sensitive as horizontal line detection so the center focusing spot Is the most accurate one to use.

We have tried dynamic focus and predictive focus, but were not impressed. We still found the best way to sharply focus action is to use the middle autofocus spot on continuous autofocus, pan with the subject, and hold the spot right on the most important part of the subject. Please check your camera to see if you can move the focus control to a button on the rear of your camera and give it a try. Most cameras can do it, but you might have to hunt to find the control. Our workshop participants love it once they get used to doing it. It is interesting that nearly all of our workshop and tour participants who mainly photograph nature have no knowledge about other options for focus control. Meanwhile, we had one pro sports photographer in our autumn color workshop who shot for Sports Illustrated who used continuos autofocus on the back button all the time. Apparently, this idea is common practice among advanced sports photographers. Hopefully, the benefits of using Back Focus as he called it will become much wider known among nature photographers.