Ten Top Auto-Focus Techniques
Peter Burian offers a range of 10 tips for maximum reliability with a DSLR camera's auto-focus modes and functions.
Approximately 26 years have passed since the first commercially successful auto-focus SLR was introduced (the Dynax 7000) and the technology has significantly improved since then. Even so, some photographers consider AF suitable only for snap shooting. Others insist that even the best systems are still far from reliable. They relate stories of missed opportunities while the AF system hunted for focus in low light or set focus for an inappropriate subject area.
That might suggest auto focus is unreliable, but it’s far from accurate. Having tested numerous 35mm and digital SLR cameras, I know the current technology is incredibly successful. Even the majority of professional photographers now admit to using AF in situations where manual focus is too slow to capture a decisive moment.
If you’re using an old camera with an outdated AF system you might not consider auto focus to be as successful. However, current models - with recent AF lenses - provide fast, reliable focus acquisition due to new technology and features. These include multi-point AF sensors, automatic or user-selected focus point selection, superior focus mechanisms in the lenses and camera bodies, and high-speed Continuous AF for tracking action subjects. Some models provide even more options, as discussed later. If you’re not fully satisfied with the focus in some of your photos, consider the following hints.
Tips For Focus
1. Don’t expect auto focus to read your mind. Even the most “intelligent” AF system can’t determine your photographic intentions! It’s designed to set focus quickly on a reliable target. In a close-up portrait mode for example, an AF system will often select the nose. In an ultra-wide composition - with subjects at various distances - the system may select one that isn’t your preferred target. When you’re shooting a car race which includes several competitors, focus is usually set for the largest central subject (with a multi-point system), even if the leader is at the side of the pack. If these problems lead you to decide that auto focus is “useless”, your expectations are probably unrealistic! While “mind reading” computers may eventually be invented, current technology requires the photographer to take some responsibility for the composition of their image. That’s arguably the way creative photographers should like it. Instead of using only a point-and-shoot approach, remain aware of the point of focus; when necessary, use one of the following overrides or techniques...
ALSO IN THIS ISSUE: Trekking in the Andes; Fine-tuning JPEG images for quality prints; Capturing images during the "magic hours"; Profile - Andrea Francolini; Locations - Yea & District, Vic; Picking the perfect camera bag; Nikon 1 V1
This story was first published in Australian Photography February 2012 issue of Australian Photography > February 2012
This story was first published in the Australian Photography February 2012 issue of Australian Photography > February 2012.