Photography 101: Understanding Autofocus and Focus Points

Your camera has a great feature called “Autofocus” which is normally set to the “on” position by default. However the settings of the auto focus can be overridden, you will need to look through your manual for the instructions on how to adjust the setting for your particular camera.  The autofocus and focus point features were designed to help photographers know where in the scene the camera is focusing the lens on. The focus points do not show up on the image, they are only visible through the viewfinder or on the LCD screen depending on the manufacturer of your camera. Most SLR and DSLRs, even most point and shoot cameras, come with Autofocus and the focus point feature in the viewfinder of them. So what are they and how can you benefit from them?

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Auto focus points generally are shown as small squares when you look through your camera’s viewfinder that are arranged on a grid that overlays the scene you are about to photograph. On some camera’s the main focus point will have a set of brackets or a circle around the middle point of the frame. Most cameras manufactured today give you a few options for the focus point grids. Some cameras have a 9 point system, while other cameras have 11, 39 or even 45 point grids. My Nikon comes with the option of 11 or 39 points.

When you press the shutter button down halfway your camera uses one of these focus points to focus the lens on a particular location in the cameras field of view, this will be your crispest spot of the photograph. The point(s) being used by the camera will be indicated by briefly lighting up in red or green depending on the camera manufacturer. If by chance there is nothing to focus on in your scene sharply, the camera will more than likely refuse to allow you to activate the shutter button fully. This “deactivation” feature mostly occurs when the scene is a little too dark for the camera to pick up on the details of your subject. The good news is the feature can be overridden in most cameras on the market today. There is another downfall to the autofocus and focus point feature, the vast majority of the time the feature is used it normally picks up the details of the large object or the closest object in your scene. For example if you are creating a landscape photograph of a mountain range on the horizon and there is a bush in the foreground, your camera will more than likely insist that the bush in the foreground is your primary subject instead of the mountain range. This could still be a beautiful image but not necessarily the one you wanted, especially if you wanted the detail of the mountain to be crisp in the photograph.

Override the Auto Focus Point Feature
There are a few ways you can change the autofocus and auto focus point features of your camera. Depending on the manufacturer of your cameras you may have the option of manual /auto focus point selection or even select a group of points. Check your manual for the correct location of the setting.  Another way to change the auto focus point is to set your camera to always use the center of the frame as the main focal point then manually move your camera. This method requires you to center your subject in the viewfinder and press the shutter button halfway to lock focus. Without removing your finger from the shutter button, recompose your shot to the position you want the subject to be in for your final photograph. Using this method doesn’t just help with focusing, it also helps to ensure better light meter readings.

About the author: Melissa Fague has been a professional nature and landscape photographer for 6 years and has won several awards, nationally and internationally over the past few years. We welcome you to read more about her story of becoming a nature and landscape photographer or to view her online art gallery.