Photography lesson - Focus

A sharply focused images is one of the main reasons people switch to dSLR photography. Digital cameras offer both manual and automatic focusing.

It takes longer to focus manually than it does to let the autofocus feature do it for you, especially for the beginner. However, in poor light or if shooting through a window the autofocus may take ages to hunt down the focus. You may also deliberately wish to blur an image and so for these reasons, the manual focus can be a real benefit.

Auto-focus is great for fast moving subjects such as wildlife or sports photography. It also allows people who still have good but no longer excellent eyesight to continue taking perfectly focused photographs.

When you take macro photos you may want to focus on a butterflies wing, but your compact camera insists on focusing on the leaf it is sitting on. This is where a dSLR will give you the control you need to take the photographs you want.

auto focus

My compact camera focused on the rose petals rather than the spider in the photo above which is not what I wanted at all..

manual focus

In manual mode with a dSLR it is easy to make sure the spider's eyes (and her lunch) are in focus.

Play around with both manual and autofocus when you are starting off with a new camera and you will quickly learn which is right for which situation. I find the autofocus option is best for about 80 to 90% of shots and the rest are manually focused.

Most dSLR cameras have at lease two automated focusing modes. These are generally center weighted and multi point. With centre weighted focusing, the sensor hunts around the image in the viewfinder, searching for something to focus on. If it finds areas of equal probability it will settle on the area closest to the centre of the picture. With multi spot focusing the sensor will hunt for the focus where as many discrete elements are in focus as possible.

Sometimes you might find part of an image is in focus while another part is out of focus. This is a good time to start reading about depth of field.