As a professional photographer, in conversation with enthusiast photographers, I’m often asked; “how can I be more creative with my camera it’s only an XYZ and doesn’t take good photos” or similar meaning phrases.
My answer is always on these lines. The one thing that will give you greater creative control in photography is an understanding of Depth of Field, be aware of it and use it. And this makes no difference if you are a working Portrait Photographer, a PR Photographer, or happy snapper taking photos of the family or doing street photography.
What is Depth of Field?
DEPTH OF FIELD
Depth of field (DOF) can be described as the nearest to the furthest distances from the lens where the subject appears in focus.
Shallow DOF is created using the widest aperture settings on the lens (F stop number). The subject behind and in front of the point of focus appears progressively out of focus. Due to the smaller sensors used in compact, bridge and consumer cameras it is often difficult to achieve shallow DOF unless you are working at the closest focusing distance of the lens, i.e. taking an image using a camera with a small sensor will lead to greater DOF than a DSLR. Using a full frame DSLR will give you a narrower DOF than using a DX DSLR with the same lens set at the same aperture.
Maximum DOF is created using a smaller aperture setting on the lens (F stop number). The subject immediately in front of the lens and subject in the distance appear sharp in the same image.
- The widest apertures (F 1.4, F 2, F 4) gives the least depth of field (big hole).
- The smallest apertures (F 16, F 22) gives the greatest depth of field (small hole)
- The smaller the sensor the greater the DOF at the same aperture
- DOF preview on some DSLR cameras – (check your manual)
Distance: As the photographer moves closer to the subject the DOF becomes narrower. As the photographer moves away the DOF becomes greater.
Focal length: As the focal length of the lens increases (telephoto lenses) the DOF becomes narrower. As the focal length of the lens decreases (wide angle lenses) the DOF becomes greater.
- The shallowest DOF is achieved with the widest aperture on a telephoto lens whilst working at the lenses minimum focusing distance.
Point of focus: Unless you are very close to your subject, you’ll find that DOF extends more behind the subject than in front. About twice the distance behind your point of focus will be in focus than in front of it.
Practical application: All factors affecting DOF are working simultaneously. The aperture remains the photographer’s main control over DOF as framing (usually a primary consideration) dictates the lens and working distance. For maximum control over DOF it is best to select aperture priority or manual mode and use a DSLR (or SLR) a rangefinder camera or any other with a larger sensor then a compact. First decide on the subject, which is to be the focus point of the image. Second decide whether to draw attention to this subject, isolate the subject entirely or integrate the subject with its surroundings. Precisely focusing the lens is unnecessary when photographing in bright conditions with small apertures (F 11, F 16 and F 22). DOF on a wide-angle lens stopped down to F 16 may extend from less than three feet (one meter) to infinity.
A good example of shallow DOF is sports photography, the photographer chooses to isolate his/her subject, using a long telephoto lens with a wide aperture, blaring the background. A landscape photographer, wanting everything from the foreground to infinity to appear sharp, and to draw the viewer into the scene will use a narrow aperture, say F 11 to F 22 and a wide angle lens.
Me, I tend to use a wide aperture for my Portrait Photography, working close to my subject, and a small aperture for PR Photography, but still working as close as I can to my subjects. When I’m out doing Street Photography, I use a 35 mm lens (on a full frame camera) at about F 8.
The featured photo was shot with a shallow DOF at F1.4 using a 58mm lens, focusing on the child dirty nails. The urban scape photo inserted into this blog was shot with a narrow DOF at F11, focusing on the house, letting the foreground and infinity to be in focus.
I hope this article has cleared the mist a little on DOF, and how to use it creatively in your photography.