Fool Your Digital Camera's Autofocus to Take Better Pictures - Good Photography Techniques & Digital Camera Tips
Some cameras have the option of manual focus and some cameras offer a multi-point focus or wide area autofocus (AF), but let’s say either: a) Your camera’s features don’t include manual focus, b) your digital camera doesn’t have AF features or c) your camera has these features but you’d rather not use them.
What’s the problem?
When your digital camera uses autofocus, the camera will focus on whatever is in the center of the viewfinder. This can be problematic when you do not want your subject to be in the dead center of your photograph, such as when you’re following the Rule of Thirds. It will result in the background being in focus but your subject being blurry. You could get lucky if your background is the same distance as your subject, but that often isn’t the case. Another example of when your autofocus could fail is when you’re taking a photo of more than one person. Even if you want those people to be centered in your photo, the space between them will surely be the AF point of your camera, causing the background to be in focus and the people to be out of focus.
So, what’s the solution?
Learning how to use your digital camera’s focus lock feature will fix the problem. Pressing the shutter button half way and holding it there will stop the camera’s AF and lock the lens focus. In most digital cameras, you’ll know you’ve “locked-down” when you hear a beep or there’s an indication in your viewfinder. So, how do you use focus lock to your advantage? Quite easily. If you’re wanting your subject to be in focus but off center, start by centering your subject within your digital camera’s viewfinder or LCD screen and press and hold the shutter button half way - locking your focus on their face or whatever your subject may be. Because you’ve locked your focus, slowly moving the camera to recompose your subject, the autofocus will remain with your subject. Now, all that’s left to do is press the shutter button the rest of the way down and you’ll now have a photo where the subject is in focus.
The following photos are by no means wonderful, but they illustrate the difference between not applying focus lock to your subject and using focus lock on your subject before recomposing. (Click on images for a larger view)
Not working for you?
If you’ve attempted the above but are still having problems, here are some ideas and tips that may help:
1. Autofocus works by moving the camera’s lens in or out, depending on the distance of the object. If you have activated the focus lock and then proceed to move closer or further away from your subject or you get your subject to move closer or away from the camera, the subject will then be out of focus. Be sure to zoom in (or out) before pressing the shutter button half way down. If your subject moves and alters the distance after you’ve initiated the focus lock, simply release the shutter button and try again.
2. What happens when you hold a book too close to your face? Try as you might - cross you eyes, wrinkle your forehead - the only way to make those words come into focus is by moving the book further from your eyes. If your camera refuses to cooperate when you try using focus lock, it could be because you are too close to your subject resulting in the camera being unable to focus. Try zooming out or taking a step back and give it another shot.
Shooting in digital has its advantages: there’s no waste or expense of film and developing, you can keep practising until you get it right. Good luck and happy shooting!