Techniques

Bird Photography Basics: A Focus on Sharper Images

by Matthew Studebaker | July 6, 2012

© Matthew StudebakerDiscerning bird photographers want their images to be of the highest quality possible, and this usually means they are striving for tack sharp details in their subject. Accurate focus and appropriate shutter speeds are essential for getting sharp, detailed images of our feathered friends.

A Word on Focus

While equipment shake may the number one culprit for soft or blurry images, inaccurate focus probably comes in as a close second. I know of no serious bird photographer who, at the time of this writing, still uses manual focus lenses on a consistent basis. Birds rarely stand still, and auto focus greatly increases the number of accurately focused images. Personally, when I manually focus, I only get about 3 in 10 photos with razor sharp focus, while auto focus often nails 9 out of 10. Auto focus technology is simply too advanced and readily available to seriously consider a manual focus lens for everyday use.

King Eider takeoff © Matthew Studebaker

King Eider – Barrow, Alaska

Tips for Acquiring Accurate Focus

First, while most modern auto focus lenses are very fast at locking on to a bird when the bird is almost in focus already, most lenses are not very good at searching great distances to find the subject. If your lens is pre-focused at 4 meters and then a falcon flies by 20 meters away, you’ll never find it in the viewfinder in time unless you manually focus to about 20 meters and then the auto focus lock on and do the fine tuning. The first rule for using auto focus is to make major focus changes by hand, but let autofocus do the micro adjustments and lock on. This principle applies no matter what camera you are using. In fact many of my most successful flight shots were made using a Canon Rebel XT. The higher end camera bodies make life easier, but the same principal applies.

Note: I now use a Canon 1D Mark IV paired with a 600mm f/4 IS lens and find this combination does an outstanding job of both instantly searching the entire focal range AND doing the small, last minute micro adjustments for sharp shots. Still, prefocusing by hand can speed along this process, particularly when the scene has a busy background or the subject is moving in and out of dense vegetation.

Long-tailed duck in Alaska © Matthew Studebaker

Long-tailed Duck – Nome, Alaska

Limiting Focal Range

Many modern auto focus lenses allow the photographer to limit the range of focus. For example, when photographing large birds far away, one could theoretically switch the lens to only focus 20 meters to infinity rather than include the closer ranges. Because auto focus isn’t very good at quickly searching the entire focal range for the subject, some bird photography teachers advise their pupils to use the range limitation feature on the lens to limit the range of focus in situations like this. The theory is that the lens will only have to search a more limited range to find the subject. The problem with this theory is two fold.

First, these teachers assume that they won’t have a surprise encounter with another bird species. For example if you were photographing a distant heron nesting colony and set your lens range to distant subjects, what happens when a small warbler lands right next to you with no warning? You try to focus but your range is limited to only distant objects. You fumble to switch your range to close subjects but by then the warbler is gone. Or what happens when an osprey starts flying directly towards you, starting in your distant range, but in a matter of seconds moves into your close range? The camera will lock the focus and you’ll miss your shot.

Second, limiting your focal range assumes that the best way to focus is to let the lens find the bird. As we already discussed, we don’t want the lens to do the range searching—that’s not what auto focus is good at. It’s only good at small micro adjustments for locking on to the subject. So if we are doing 95% of the range searching manually anyway, there’s no need to limit the auto focusing range. Keep the range unlimited. Do the major focusing adjustments by hand. Depress the shutter half way and only let your auto focus take over and lock on at the last second.

Common nighthawk in flight, Montana © Matthew Studebaker

Common Nighthawk – East Glacier, Montana

Focus Confirmation

There are two types of focus confirmation commonly available in today’s cameras. The first is a small beeping noise which sounds when focus has been acquired. This noise is soft enough that it would only bother the most shy of birds. In fact, many birds, if they hear it, are curious and give the perfect head turn towards the camera just as you acquire focus. Sometimes it’s great. Sometimes it’s annoying. Once in a while it scares the bird. I usually leave my confirmation beep turned off because I find the noise annoying.

The feature I do appreciate in modern cameras is the focus sensor light. In my sensor array, the sensor(s) which has locked focus turn red for about a half of a second. This lets me know more specifically what exactly the camera is locking on to, and is much less annoying that the beep confirmation.

Wood duck in Ohio © Matthew Studebaker

Wood Duck – Cleveland, Ohio

Shutter Speed

Another critical factor in producing sharp images is using sufficient shutter speed to stop both the motion of the bird and the movement of the lens. IS and VR (Image Stabilization on Canon, Vibration Reduction on Nikon) helps cut down on lens vibrations and the negative camera shake on the photographer’s end, but can only go so far. A fast enough shutter speed is critical for sharp shots. Using the right shutter speed is somewhat of an arbitrary judgment call learned with practice, as every lighting situation, bird movement, and photographer is different. There are, however, some basic guiding principles which are universal.

First, lens length and required shutter speed are directly related. In other words, as lens length increases, shutter speed needs to increase in order to compensate for the “magnified vibrations.” Your own experience will verify this. If you look through a wide angle lens, the image in the viewfinder will appear fairly stable. If you are looking at the same scene through a telephoto lens the image in the viewfinder will appear as if you are violently shaking by comparison—the image is magnified but so are the vibrations. To compensate for these vibrations an increase in shutter speed (i.e. decrease in exposure time) is needed so that the vibrations don’t end up effecting the image sharpness, blurring the image.

Second, amount of subject movement and the required shutter speed to freeze that movement are also directly related. The faster your subject is swimming, flapping, running, or flying, the faster the shutter speed will need to be. I find that most normal bird behavior is frozen at 1/500 second or faster. Most flight shots and wing flaps are frozen at 1/1000 or greater. Hummingbird wings can be mostly frozen anywhere between 1/1500 and 1/16000 of a second, depending on where their wings are in their figure 8 motion and the size of the bird. Hummingbird wings slow down at the full upward and full downward wing positions, but are incredibly fast in between.

Indigo bunting in Ohio © Matthew Studebaker

Indigo Bunting – Cleveland, Ohio

Conclusion

While there are more factors involved in making sharp images, accurate focus, fast shutter speed, and vibration reduction all play a critical role. By understanding the mechanics of each factor and how to best utilize technology and your equipment, you can maximize your chances of success.

Red-tailed hawk, Ohio © Matthew Studebaker

Red-tailed Hawk – Cleveland, Ohio

About the Author

Matthew is a professional nature photographer living in Cleveland, Ohio. He leads a number of bird photography workshops around the U.S. For more information please visit his website: www.studebakerbirds.com.

Post a Comment

Logged in as Anonymous