Tip Eight – Focus!
This is tip eight in a series about photography called, “Ten Things All Photo Geeks Must Know.” It is for the more serious amateur photographer who shoots with a digital camera. These ten tips are the basis for a solid foundation in photography. Once you have these skills in your proverbial camera bag you will be able to advance quickly. Some of the posts will apply to film cameras as well but I am writing this series with an aspiring digital photo geek in mind.
Our amazing human eye can take in a whole scene, effortlessly keeping both the foreground and the background in focus. But, achieving a properly focused image with a digital camera takes effort and skill. It is worth mastering, though, because when you enlarge and print images, a blurry subject becomes a real eye sore.
When I was learning about photojournalism at the University of North Carolina at Chapel Hill we heard a slogan, “F/8 and be there.” This was said by Arthur “Weegee” Fellig, one of the founders of documentary photography when asked how he was able to consistently get sharp images even of quickly changing scenes. He was referring to a technique called zone focusing that predated the days of auto focus. Nowadays you can achieve properly focused images in three ways:
Manual focusing is exactly what it sounds like. Click the auto focus off on the lens barrel and manually turn the focus ring until your image is sharp. When I was fresh out of college and was working at The News & Observer I was watching all the seasoned photojournalists like a hawk so I could learn as much from them as possible. I remember one co-worker used his down time to simply look through the lens and pan around the room focusing quickly on a wide variety of objects, honing his manual focus skills. With practice you easily learn which way to turn the focus ring and are able to get sharp images in even fast-moving situations.
Zone focusing takes advantage of what is called the hyperfocal point. Basically, all lenses of a given focal length and aperture when focused to a specific point will have a zone of focus in which items in that zone will appear in sharp focus. As an example a 35mm lens set at f/8 and focused to about 17 feet will have everything between 9 feet to infinity in reasonably sharp focus. Hence the f/8 and be there.
On the other hand, a 50mm lens set to the same values would have everything from 11 feet to 34 feet in focus, while a 21mm lens would have everything from 4.5 feet out to infinity in focus. Most prime (non-zoom) lenses show the zone of focus at a given aperture on the lens barrel. This is that list of numbers that seem to repeat on the lens symmetrically.
For many years I eschewed auto focus as the easy way out. But now I am in love with it. At almost forty years of age, I could use a little help here and there. Most digital cameras show a grid in the lens finder. On my Canon, to use the auto focus I make sure the auto focus is on (there is a switch on the lens), I press an auto focus button and toggle over to which ever part of the grid I want to be in focus. The camera does all the rest of the work for me. If you really want to become a master of your auto focus it is worth taking out your camera manual and slogging through that section. My camera even has three kinds of auto focus depending on whether the subject is moving or stationary.
Let me show you one quick example. In the image above I am on my stomach using my elbows as a tripod. My son, Roman, has just finished a marathon session of building two lego pirate ships. I was using a 35mm lens set to f/5 at 1/125th of a second. I did not focus correctly! The sharp part of the image is on the bow of the first ship. I would have preferred to have had the focus on his face.
In this image, I manually focused the image to make sure that his face was in focus. I also could have used auto focus or zone focusing.
If you missed the seventh part of this series, read it HERE. It would also be helpful to have read the second part of this series, all about aperture, to fully understand this blog post. Please be sure to ask any questions you may have! I am also always open to suggestions for photo stories. You may contact me via email. If you don’t want to miss any Snapshots from the Hill posts, please subscribe to the RSS Feed.
Thanks for reading!