Depth of Field 101

Below are some notes from my Fundamentals of Photojournalism class at the University of Missouri School of Journalism. I am blogging about this to improve my retention of what I learn in class.

Basic Depth of Field 101

1) Three things affect Depth of Field.
Aperture
Focal length of the lens (i.e. 50mm, 35mm, 135mm)
Distance from the subject (greater the distance the the shallower the depth of field).

2) Focusing should always be done on the eye. The eye always needs to be sharp. For portraits the subject should be in focus and the background should be as neutral/fuzzy as possible. This will bring attention to the subject.

3) Shutter is the duration the camera window is open.

4) All the stops are half or twice as big as the previous. So if you make the shutter faster you need to compensate by changing the aperture or ISO.

New info to me.

Today I actually learned something I have never heard about before. It is called the Depth of Field Preview button. It was mentioned casually in class but I found more about it online. There is a great article here. I am excited to start using this more. It is sad that I haven't heard more about this before, because I have been taking pictures now for almost a year and a half.

Another thing I learned is that the f stops are really not a fraction but rather an logarithm.