Shooting in Aperture Priority Mode

Jeff Cable

More and more people are upgrading from digital point and shoot cameras to the now more affordable digital SLR cameras. Many people are attracted by the option of interchangeable lenses and increased creative control of the SLR cameras but many are often confused by all the options that come with this newfound tool.

Although the digital SLR can capture great images when left in the automatic mode, it is much more fun and interesting to use the camera to control the outcome of your images.

I have always loved taking pictures of people and animals and I remember the first time that I captured a picture of my kids where the children were in focus and the background was soft and blurred. This image focused all the attention on my kids and not on the trees in the orchard behind them. This image was captured in automatic mode and it was more luck than skill.

Captured at f6.3 (notice the muted background). This tall weeds in the background would have been distracting to this picture if they were in perfect focus.

From the time that I viewed this image on my computer I was determined to learn how to create this affect and not rely on luck.

First, I had to make the big step and switch my camera to aperture priority (usually represented by AV). Then I had to do the unthinkable and read camera manual to learn how to adjust the aperture setting. I changed the aperture to the lowest number (the more expensive lenses will let you shoot at 2.8 or even lower). The lower the number will give you the least "depth of field" which means that you will have the greater degree of change in focus from objects that are closer to you from their background. Then it was time to experiment with this technique. The best way to do this is to stand close to your subject and have the background far from the subject.

You will notice in this example that the background is blurred and soft in the image shot at f4.0 while the image taken at f22 is focused throughout.

Try shooting the same subject with different aperture settings. You should see a big difference between shots taken with f4.0 and f22. Once you get used to shooting your pictures this way, you will most likely get the craving to purchase a more expensive lens that will let you shoot at f2.8 or even f1.4.

A word of caution when shooting at f4.0 or lower: Because you have a greater degree of focal change, you have to be more careful on which parts of your subject are in focus. When taking a picture of a face, you might want to focus on the eyes and have the other parts of the face slightly softer. If you want to get all areas of the face in perfect focus, you might want to shoot your picture at f11 or even f22.

The great thing about digital cameras is that you can experiment and not worry about the high cost of film. You also get immediate results on the LCD of your camera and can make adjustments right away. I encourage you to put your camera into aperture priority and give it a try.