Introduction - A way of seeing - 3

Project: Focus

Exercise: Focus at different apertures

At first, this exercise seemed easy, although I never experimented enough with different apertures. But when I started taking the photos, I realized I had to work harder than expected. I took about six or seven sets of pictures, and even the final result was not as good as I hoped. I photographed trees, letters in a row, fences, bridge pillars etc. I couldn't see the difference in depth of field size, clear enough. I was using a wide lens (11mm focal length). So finally I decided to switch for a 50mm lens, with which I could see some results.

First photo bellow is taken at an aperture of 2.0. The area that is in sharp focus is rather small, just around the focus point. I traced some limits, in dark gray, and I marked the focus point.

Focus at different apertures - f 2

The second photo is taken at an aperture of 7.1, and the area in focus in bigger, maybe about twice as big as in the first photo.

Focus at different apertures - f 7.1

And the last photo is taken at an aperture of 22, and the area in focus is large, encompassing almost the entire picture.

Focus at different apertures - f 22

I think this was a very useful exercise for me. I have a much clear picture in my mind now. And I think I'll be more successful in the future, when taking photographs of landscapes or groups of people. It feels good to have more control over the area that you want to be in focus.

I remember now what I learned in the past about the depth of field, being twice as large behind the subject than in front of it. And I think the photos above can show this rule pretty well.