AYN Advice

Help me understand more abour camera ‘focus’.

How much better is a sharp image than a blurry one? Much, once you get used to the difference. But, you say, the camera does the focus for me. It’s all automatic, so what can I do? Even with a completely automatic camera you do have some control.

Most cameras work so that when you push the shutter button half way, the built-in meter reads the exposure and measures the focus. Usually the focus is measured at the center of the image so whatever is in the middle of your picture is what the camera will use to focus on.

Let’s say you have a person standing ten feet from the camera in the right half of the image. Ten feet behind the person in the center of the image you have a tree. If you just point and shoot, the camera will focus on the tree and the person will be blurry. What is the subject of this picture, the tree or the person? If the person is the subject, you need to use this technique to keep an off-center subject in focus. Point the center of the camera at the person’s head and press the shutter button half way. Wait while the camera focuses the image. Then WHILE HOLDING the shutter button half way reposition the camera to center the tree and press the shutter button completely to take the picture.

Now you have the person off center which creates dynamic tension and is a visually strong type of composition. You also have the tree in the center of the image where the mind expects the main subject to be but slightly out-of-focus thus adding to the visual tension while not distracting from the subject.

Does your camera have modes: portrait or landscape mode? If you use portrait mode only the point of focus will be sharp and anything in front or behind the point of focus will be blurry. This effect is called a shallow depth of field. Depth of field is a measure of the amount of depth in the image that is in focus. The camera achieves a shallow depth of field by using a large aperture in the lens. This effect or mode is ideal for portraits because the person, the subject, is in focus while the background is thrown out of focus. An out of focus background is less distracting and allows the subject to play center-stage in the photo.

With landscape mode it is just the opposite. Most of the image will be in focus. This effect is called a large depth of field and the camera achieves this by using a small aperture in the lens. This effect or mode is ideal for landscapes where generally you want most or all of the image in focus.

If you have these modes, choose your mode according to whether you want little or much of the image to be in sharp focus. Portrait mode can be used for other subjects besides people; animals, flowers, objects or any subject where you want the background and foreground to blur out.

If you want most of your image to be in focus whether it be a landscape, a building, a home interior, or an article to sell on ebay, use landscape mode and focus on the subject or about 1/3 of the distance into your image.

The important point to remember is to focus on your subject first then while maintaining pressure on the shutter button reposition the camera to obtain the desired composition and press the shutter completely.

If you wish more information on this subject, there will be a future topic on ‘Working with Depth of Field’.