How To Wednesday: Depth of Field

Recently, a few clients have commented that they love the images with the softer/fuzzier backgrounds … so for the next two segments, I thought I’d give a brief introduction into how that ‘effect’ is created.

Part of what they are referring to is known as Depth of Field. You don’t have to have a fancy camera to achieve it either — before I had a DSLR, I was able to capture images with softer/blurred backgrounds with a point and shoot camera set in auto or macro modes. I will say its a bit easier with a DSLR, but it can be done with a P&S.

I’m not going to go into the technical aspects of how to achieve this other than explaining quickly in terms of DSLR/film SLR capabilities. But I will show you a variety images with different depths of field.

With a DSLR/Film SLR, when shooting in non-auto modes that is, you have control of three things: shutter speed, aperture, and ISO. For purposes of today’s how to, aperture is the primary setting/function that you need to understand in order to achieve different ranges of depth of field (I’m skipping over the other two for another how to later on). High aperture (which is actually a low number, such as f/1.8 or f/2.0) allows for a shallow depth of field, where as a low aperture (a higher number, such as f/8, f/11, f/22) creates sharper backgrounds.

For portraits, I almost always use a ‘higher’ aperture unless I’m wanting to capture one of two things: (1) the setting around the subject or (2) really cool lens flare. By higher, usually I’m shooting anywhere from f/1.8 to f/3.5 depending on which lens in the arsenal I’m shooting with.

Here’s a few examples of shallow depth of field versus a deep depth of field. All of these were shot full manual … I’m including the settings, lenses, and the camera models for the curious.

 

ISO 250, 1/320 @ f/2 (Canon 135 mm f/2L on Canon 5D)

ISO 250, 1/320 @ f/2 (Canon 135 mm f/2L on Canon 5D)

These two above were shot at sunset … other than enhancement of color (or conversion to an artsy b/w), the depth of field is as it was SOOC (straight out of camera).

ISO 250, 1/320 @ f/4.5 (Tamron 28-75mm f/2.8 on Canon 5D)

ISO 250, 1/320 @ f/4.5 (Tamron 28-75mm f/2.8 on Canon 5D)

Note that you can somewhat tell what’s in the background of these two in comparison to the two portraits above. I did do an artsy edit to these, which added ‘grain’ to the image more than anything.

… and a few examples of a deep depth of field …

ISO 100, 1/250 @ f/4 (Tamron 28-75mm f/2.8 on Canon 40D)

ISO 100, 1/250 @ f/5.6 (Tamron 28-75mm f/2.8 on Canon 40D)

ISO 125, 1/250 @ f/10 (Tamron 28-75mm f/2.8 on Canon 5D) — this one was taken on a harsh sunny day in comparison to the other images pictured

ISO 400, 1/250 @ f/11 (Canon 28-105mm f/3.5-5.6 on Canon 40D)

Note on all of these that all the details, near and far are sharp/in focus compared to the first four pictured.

There are a great deal of websites and how to books out there that go much further into the technical aspects of this — just do a search for “depth of field”. For the P&S users out there, I’ll try to unearthen some p&s pics and share them on Friday if I have a few minutes to spare!

Next month I’ll cover the other ‘effect,’ bokeh …