05.11.2020

Prefocusing vs Autofocusing

Prefocusing and Action Photography

A great way of shooting sports and wildlife photography is to prefocus at a point where you know the action will be taking place, then wait for your subject to come to you. This could be a BMX rider or skateboarder pulling a midair trick, in which case you’d prefocus on the apex of the ramp. Or it might be a downhill skier passing a point on a slalom course, which you’ve focused on well in advance of them getting there.
 
As the subject reaches the prefocus point, you can squeeze off a burst of frames using your camera’s fastest continuous shooting speed, and be confident the first image in this sequence will be as perfectly timed as your human reactions will allow.

© Michael Clark

Wildlife photographers also use this technique to photograph subjects such as birds arriving back at their nest or butterflies landing on a flower, which can happen suddenly and without warning. Just prefocus on the spot where they will land and you’re ready to shoot – with a much-improved response time.
 
Prefocusing doesn’t have to mean focusing manually, mind you. If you’re a fan of back-button focusing, then you can use this as a way of prefocusing with AF. Once you’ve focused, your camera won’t attempt to focus again when you shoot, so you’ll get the response time advantage.

Prefocusing and Street Photography

Street photographers have also traditionally used prefocusing to improve response times (after all, the phrase ‘decisive moment’ sprang from this discipline), but they do it slightly differently. Being on the move all the time, it’s impossible to prefocus on a specific place, so instead they prefocus at a distance and use depth-of-field to ensure the objects just in front and just behind this distance are sharp.

High contrast black and white street photograph of silhouette of man walking on pavement - taken from an elevated position through the glass barrier of a balcony
©Rinzi Ruiz

For instance, by focusing manually at distance of 10ft with a 23mm lens and setting an aperture of F8, everything from 6.5ft to 16.5ft will be acceptably sharp. All this without the need to autofocus, so you can enjoy the fastest response time your camera has to offer.
 
To do this, you’ll need to make sure the camera’s focus scale is showing in its viewfinder or on its rear LCD. Press MENU OK and go to SET UP > SCREEN SET-UP > DISP. CUSTOM SETTING and make sure that MF DISTANCE INDICATOR is ticked.

Learn photography with Fujifilm, Prefocusing vs Autofocusing

Now when you’re in manual focus mode, you’ll be able to set a focus distance by looking at the scale. The blue area either side of the focus distance indicator is the zone of acceptable sharpness given by the current depth-of-field.

Learn photography with Fujifilm, Prefocusing vs Autofocusing

It should be noted that the phrase ‘acceptably sharp’ is subjective, and depends on what you plan to do with your photos (print or screen) and how much you value perfect timing over perfect focus. In fact, your camera’s depth-of-field scale can be configured to show you what will look acceptably sharp when you make prints or what will look acceptably sharp when you examine images on screen at 100% (sometimes called ‘pixel peeping’).
 
To switch between these two modes, go to AF/MF SETTING > DEPTH-OF-FIELD SCALE and choose either PIXEL BASIS or FILM FORMAT BASIS.

Your Next Steps

  • CHALLENGE Spend a day making images with and without prefocusing and compare the results. Post your before and after shots to social media using the hashtag #MyFujifilmLegacy. You can also submit your work here for a chance to be featured on our social media channels.

Head Image ©Karen Hutton