you're reading...

Learn By Doing Photography

Circles of Confusion

This past week we did an aperture assignment to see what would happen if we set up our camera on a tripod and took a few picture on aperture priority. The only setting we changed was our aperture by 1 stop each time. Result – The wider the aperture the more shallow depth of field you end up with.

After reading up this week as to why this happens I came across many posts that talked about the circle of confusion. This circle confused me even more.  What I did learn… there are three factors that influence depth of field:

  1. The focal length of your lens
  2. The distance between you and the subject
  3. The aperture you select

This week we’re working with aperture settings.  The best example I came across was actually in a book – Understanding Exposure by Bryan Peterson – Quoted from the book:

“Imagine using a funnel with a very small opening and pouring a one-gallon can of paint  through it in to an empty bucket. Compare this process to pouring a one-gallon can of paint in to the same empty bucket without the aid of the funnel. Without the funnel, the paint gets into the bucket quicker, but it also splatters up on the bucket sides, as well. With a funnel, the transfer of paint to the bucket is cleaner and more contained.”

What a great visual! When you use a smaller aperture like f/22 your pictures will come out neat and sharp, but if you want to add a dash of blur to your image open wide and go for that splash with a f/2.8 or f/5.6.

Of course that is only one piece to the puzzle when it comes to depth of field we still have focal length and distance between you and the subject, but it’s a start!

For a great technical resource check out Cambridgeincolour I thought they did a great job explaining Depth of Field!

Related posts:

Bought the T3i ended up with the 60D
Five different snow exposure examples!
Learn By Doing - Easter Day


No comments yet.

Post a Comment

CommentLuv badge