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I love to play with Depth of Field.  If done right, it can turn a good image into a great one, and a great image into a fantastic one.

Most of the time though I don’t realize how the image will come out until I get it back or transfer it to a computer.

First of all, what is depth of field?  Simply put, when you take a picture, part of the image is in focus, and part is not.  The distance from the camera that is in focus is usually referred to as the depth of field.

This is my favorite photo to use as an example:

(click for larger version, I’ve resized this to 600 pixels wide instead of my normal 500 to show extra detail)

This is an excellent image to describe depth of field.  It is very easy to see the out of focus foreground, and also see where it goes back into focus around the diver (who is the center of focus for this image).  Then the background becomes a little fuzzy.  As an aside (and reference to a previous post), this was not taken with an amazing top of the line camera.  It was taken with a 3 MPix Canon S30, which was introduced in 2001.  Canon usually makes a water proof case for their point and shoot cameras, and I was using this case (hence the reason I had the camera out in the rain and near the surface of the water).  I was also about to go diving and I had my camera with me.  The camera was about 6in above the surface of the water.  Everything else was set to ‘auto’.

So now that we all are on the same page on Depth of Field, here is how I personally use Depth of Field.

I like to de-emphasize that which the viewer would normally consider important in favor of that which would normally be un-important.

(click for larger version)

This is a picture I took in 2003 at the Al Hambra in southern Spain.  The background is the Al Hambra, one of the most important sites in all of Spain.

By focusing on the flower, I de-emphasize the castle.  Your eye goes right to the flower and the great historical and cultural landmark becomes nothing more than the background for a relatively unimportant flower.  It also makes for a much more interesting photo if it is not all crisp and in focus.  If you want to make it all in focus, take a few steps back and use more zoom.  To get everything in focus, you need your main object to be at or past where the lens will focus to infinity (my older lens is at about 11 ft, my current is around 20 ft, my 300mm lens is at around 55 ft, most point and shoot cameras will be around 5-6 ft).  But if everything is in focus, the image will be much, much more boring.

So that is how I like to use it.  But the question is – how do you get this effect?  By knowing and abusing depth of field.

The question I have is this – are two photos, one taken from 10 ft at 50mm and one taken from 20 ft at 100mm the same?  Once you understand Depth of Field, you will begin to know that while mathematically the two images are the same, they are only the same for the main point of focus.  If you are taking a picture of a wall, then, yes, these two are the same.  But if you have objects behind or in front of your focus target, they are not the same.

And so, the next time you are going to take a picture, try to make things out of focus.  Once you get some practice, I think you will like the results.

-sdo

PS: I’ve started a Flickr account.  http://www.flickr.com/photos/38699373@N08/, although its nothing special yet.

This entry was posted on Monday, June 1st, 2009 at 4:57 pm and is filed under Black and White, Color, Photography. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.