Depth Of Field: Ultimate guide For Photographers
Understanding depth of field (dof) and being able to implement it in your own photography is an essential part of your journey towards technical competency and artistic freedom.
This guide will break down depth of field in photography and show you how to make use of it to produce fantastic landscape, portrait and architectural photos.
What Is Depth Of Field?
Before I spill the beans on how to control depth of field in camera we need to understand it in a clear and unambiguous way.
Depth Of Field defines the area of apparent sharpness, both in front and behind the point of focus, in a photo.
Everything outside this area of apparent sharpness will be rendered, to varying degrees, out of focus.
Actually, there’s only one portion of your photo that’s critically sharp: the point at which your camera’s lens is focused.
In the case of a portrait that would, most likely, be the eye that’s closest to the camera.
Depth Of Field In Camera
There are three elements by which you can control depth of field in camera. We can list those elements as follows:
Lens Focal Length
Camera to Subject Distance
Let’s explore how mastery over each of these separate elements will allow you to control depth of field and, as a result, make a huge difference to the quality of the photos you make.
Aperture and Depth Of Field
A physically wide lens aperture (e.g., f/4) will produce a relatively shallow depth of field and, as such, is often a great starting point for portrait photography.
A physically narrow lens aperture (e.g., f/11) will produce a larger depth of field with more of the photo, both in front and behind the point of focus, rendering relatively sharp.
When To Use A Large Depth Of Field
An aperture in the f/8 to f/11 range is, therefore, a great option for landscape and architectural photography.
That’s because most folks want to make landscape and architectural photos that are sharp from foreground right through to the distant background.
The image at the top of this post, featuring the Globe Tavern in Stanley in the Falkland Islands, was made with a large depth of field for maximum image detail.
As you can see the photo is sharp from the fine grained gravel foreground right through to the tree branches in the background.
Lens Focal Length
On a 35 mm film-based camera or a full frame digital camera a 50 mm lens is considered a normal or standard focal length.
That’s because it approximates the perspective with which we might expect our subject to appear in relation to their surroundings.
There are several kinds of zoom lenses, the most popular of which we can place into the following groups:
Wide-angle (e.g., 17-35 mm)
Telephoto (e.g., 80-200 mm)
Wide-angle to tele (e.g., 24-105 mm, 24-200 mm)
Theoretically wide angle focal lengths (e.g., 17 mm, 24 mm, 35 mm) produce a larger depth of field, at a given aperture and camera-to-subject distance, than would be the case with a standard focal length (e.g., 50 mm) or telephoto (e.g, 70 mm, 200 mm) lens.
Conversely, the more you zoom in the more shallow the depth of field becomes.
Depth Of Field With Macro Lenses
That’s very much the case with the photo of the rain drops on the red rose which I made in the garden of a winery in the Yarra Valley just outside of Melbourne, Australia.
I made the photograph with a Canon 180 mm Macro lens positioned very close to the subject.
This particular lens functions as both a macro lens, for close up photography, and also as a fixed/prime 180 mm telephoto lens.
All lenses have a minimum focus distance.
Macro lenses offer very high levels of sharpness and extremely high resolving power. But what makes them special is that their minimum focus distance is substantially less than what you get with other lenses.
As a consequence a macro lens allows you to photograph very close to your subject, which makes it appear larger in the frame compared to what it would if photographed from, say, one metre away.
Just be aware that the closer to your subject you get the more shallow the depth of field will be.
As you tend to work at very close camera to subject distances when using a Macro lens the depth of field produced is, therefore, very shallow indeed.
Likewise, the closer you get to your subject the more shallow the depth of field will be produced.
This is critical information because an aperture of f/4 may not produce the amount of blur you desire for a particular image.
To produce an even more shallow depth of field it’s simply a matter of moving closer and refocusing on your subject to significantly blur the surroundings.
In the case of portrait photography a very shallow depth of field will often produce a more professional looking result.
Using Depth Of Field Creatively
You can see, from the photo of the two horses, how visually powerful depth of field can be.
In this case I utilized a wide aperture (i.e., f/2), a telephoto lens (i.e., 85 mm) and a relatively close camera to subject distance to produce a very shallow depth of field.
To make the image as interesting as possible I played with the idea of similarities and differences.
Both horses looked very much the same, in reality, but by rendering one of them sharp and the other blurred I was able to provide visual separation between them.
In doing so I believe I’ve produced an interesting and, to my mind, emotionally compelling image.
Understanding Depth Of Field
Understanding depth of field is an important step on the road to mastering your camera and lenses.
As it’s also one of photography’s most creative and easily accessible techniques, proper application of depth of field will help you control the look and emotion within your own photos.