The way a subject is reproduced in a photograph can be very different from how it looked to you as you took the picture. When you cast your eye over a scene, everything in it seems more or less equally sharp, but sometimes in the finished shot only part of the subject appears acceptably sharp.
This zone of sharpness is called the depth-of-field, and it extends in front of and behind the point that you actually focused on. The size of the zone is determined by three key factors - the aperture of the lens, the focal length of the lens used, and the distance you are from the subject. Varying these three elements allows you almost complete control over the depth-of-field in a picture.
When most of the picture is sharp, we say there's lots of depth-of-field. When only part is sharp, we say depth-of-field is limited. As we'll see later, whether you go for extensive or limited depth-of-field depends upon the subject matter and how you want to depict it.
Three main factors that can be used to control depth-of-field
Excuse the state of this old Nikon lens, but it helps to show what we're talking about and by blurring the surrounding area it's easy to show the scale and depth of field. Look at the picture with the lens set to f/22. At this setting the lens will ensure everything from infinity (the symbol that looks like a figure eight on its side) to two feet is sharp. With the lens set to f/8 the zone of sharpness is reduced to infinity to just over five feet.
2 The focal length of the lens.
Here I've illustrated the affect of using a different focal length. A Nikon 28mm wide angle at f/22 would as we've seen give a sharp result from two feet to infinity; a 55mm Micro Nikkor from seven feet to infinity and a 105mm Nikkor from about 28 feet to infinity .
|3 The Camera-to-Subject Distance |
For various technical reasons, the closer you get to the subject the more limited the depth becomes. In fact, when shooting close-up subjects it can extend to just a few millimeters in front of and behind the subject.
So that's the theory, but what does it all mean in practical picture-taking terms?
Four common techniques using depth-of-field
A small aperture was used to ensure the foreground stones were as sharp as the ones in the distance.
|You can guess the hyperfocal focusing distance, but life is much easier if your lens is marked with a depth-of-field scale. This used to be regarded as an essential feature, but with the development of wide-ranging zooms many manufacturers now omit one. If you do have such a scale, simply line up the infinity mark against the mark for the aperture you've set and, although the image in the viewfinder will look out-of-focus, the finished image will be sharp from front to back.|
If you focus on infinity all the potential sharpness beyond infinity is wasted and the closest zone of focus, on this 28mm example, is about four feet.
Adjust the lens so that the infinity setting is on the marking of the aperture you have selected to extend the zone of sharpness to about two feet.
|2 Main subject sharp with background completely out-of-focus. |
There are some subjects where you want the main subject to stand out strongly from an out-of-focus background. Portraiture, where the emphasis is on the person, rather than the location, is probably the most popular area. What you need here is a use a telephoto lens at its widest aperture. It's also worth moving the subject as far away as possible from the background - in cramped studio situations this is often impossible but outside against a wall or foliage it's usually easier. Take care, though, that you focus accurately, as the limited depth-of-field will be unforgiving of any focusing errors. For portraits focus on the eye for the best results.
Plants often have distracting backgrounds so focusing on the flower head and throwing the background out is a common technique used to isolate the subject.
|3 Main subject sharp, with background out-of-focus but still recognisable. |
Sometimes throwing the background completely out-of-focus is going too far. You want to show the subject in its natural environment, but with the background toned down to it doesn't compete for attention. A person on the beach, for instance, an animal in the zoo, or a flower in a garden. Here a standard to short telephoto lens, somewhere from 50mm to 135mm, is ideal - especially if it's coupled with a middle range aperture of around f/8.
In this shot of hay the background has been deliberately pushed out of focus but not by too much so that it is still obvious what it is.
|4 Zone of sharpness deliberately limited. |
Occasionally you may want to limit the depth-of-field to a very specific zone. Maybe in a portrait you want just the eyes in focus, and not even the ears or the tip of the nose. Here, once again, a depth-of-field scale on the lens helps, or, failing that a depth-of-field preview facility on the camera, This will give a visual indication of what will and won't be in focus by manually stopping down the lens.
A technique used by many flower photographers is to really limit the depth of field. Here just the stamen is sharp making the foreground and background petal really soft.
I want to shoot with a narrow depth of field. So, I add a telephoto lens to my camera but now to get my subject in the viewfinder, I have to stand about 50 feet away. Can I add a wide angle lens in front of the telephoto lens so I don't have to stand so far away?
Thank you for your comments.
Printing Service | Online Print Shop Management System
Custom Sticker Printing | Sticker Printing companies
Albuquerque Printing Company Arizona Printing Company Atlanta Printing Company Austin Printing Company Baltimore Printing Company Boston Printing Company Charlotte Printing Company Chicago Printing Company Cleveland Printing Company Colorado Printing Company Columbus Printing Company Dallas Printing Company Denver Printing Company Detroit Printing Company Houston Printing Company Indianapolis Printing Company Jacksonville Printing Company Kansas City Printing Company Las Vegas Printing Company Los Angeles Printing Company Louisville Printing Company Memphis Printing Company Miami Printing Company Milwaukee Printing Company Minneapolis Printing Company Nashville Printing Company New Orleans Printing Company New York Printing Company Oakland Printing Company Oklahoma City Printing Company Philadelphia Printing Company Phoenix Printing Company Pittsburgh Printing Company Portland Printing Company Sacramento Printing Company San Antonio Printing Company San Diego Printing Company San Francisco Printing Company San Jose Printing Company Seattle Printing Company Washington Printing Company Toronto Printing Company Vancouver Printing Company Calgary Printing Company Edmonton Printing Company Winnipeg Printing Company Ottawa Printing Company Montreal Printing Company Quebec Printing Company St John's Printing Company Saskatoon Printing Company Regina Printing Company
Albuquerque Sticker Printing Arizona Sticker Printing Atlanta Sticker Printing Austin Sticker Printing Baltimore Sticker Printing Boston Sticker Printing Charlotte Sticker Printing Chicago Sticker Printing Cleveland Sticker Printing Colorado Sticker Printing Columbus Sticker Printing Dallas Sticker Printing Denver Sticker Printing Detroit Sticker Printing Houston Sticker Printing Indianapolis Sticker Printing Jacksonville Sticker Printing Kansas City Sticker Printing Las Vegas Sticker Printing Los Angeles Sticker Printing Louisville Sticker Printing Memphis Sticker Printing Miami Sticker Printing Milwaukee Sticker Printing Minneapolis Sticker Printing Nashville Sticker Printing New Orleans Sticker Printing New York Sticker Printing Oakland Sticker Printing Oklahoma City Sticker Printing Philadelphia Sticker Printing Phoenix Sticker Printing Pittsburgh Sticker Printing Portland Sticker Printing Sacramento Sticker Printing San Antonio Sticker Printing San Diego Sticker Printing San Francisco Sticker Printing San Jose Sticker Printing Seattle Sticker Printing Washington Sticker Printing Toronto Sticker Printing Vancouver Sticker Printing Calgary Sticker Printing Edmonton Sticker Printing Winnipeg Sticker Printing Ottawa Sticker Printing Montreal Sticker Printing Quebec Sticker Printing St John's Sticker Printing Saskatoon Sticker Printing Regina Sticker Printing
Albuquerque Sticker Arizona Sticker Atlanta Sticker Austin Sticker Baltimore sticker Boston sticker Charlotte sticker Chicago sticker Cleveland sticker Colorado sticker Columbus sticker Dallas sticker Denver sticker Detroit sticker Houston sticker Indianapolis sticker Jacksonville sticker Kansas City sticker Las Vegas sticker Los Angeles sticker Louisville sticker Memphis sticker Miami sticker Milwaukee sticker Minneapolis sticker Nashville sticker New Orleans sticker New York sticker Oakland sticker Oklahoma City sticker Philadelphia sticker Phoenix sticker Pittsburgh sticker Portland sticker Sacramento sticker San Antonio sticker San Diego sticker San Francisco sticker San Jose sticker Seattle sticker Washington sticker Toronto sticker Vancouver sticker Calgary sticker Edmonton sticker Winnipeg sticker Ottawa sticker Montreal sticker Quebec sticker St John's sticker Saskatoon sticker Regina sticker
Toronto Printing Vancouver Printing Calgary Printing Edmonton Printing Winnipeg Printing Ottawa Printing Montreal Printing Quebec Printing Saskatoon Printing Regina Printing
Albuquerque Sticker Arizona Sticker Atlanta Sticker Austin Sticker Baltimore sticker Boston sticker Charlotte sticker Chicago sticker Cleveland sticker Colorado sticker Columbus sticker Dallas sticker Denver sticker Detroit sticker Houston sticker Indianapolis sticker Jacksonville sticker Kansas City sticker Las Vegas sticker Los Angeles sticker Louisville sticker Memphis sticker Miami sticker Milwaukee sticker Minneapolis sticker Nashville sticker New Orleans sticker New York sticker Oakland sticker Oklahoma City sticker Philadelphia sticker Phoenix sticker Pittsburgh sticker Portland sticker Sacramento sticker San Antonio sticker San Diego sticker San Francisco sticker San Jose sticker Seattle sticker Washington sticker
Print Trade | Print Wholesale | Print Outsource
Add your message
428 MTF tests
74 in-depth photodo reviews
100+ users join each day
Help the lens community by reviewing or rating a lens today via our lens search
- Sigma 18-200mm f/3.5-6.4 DC Macro Lens Review
- Tokina AT-X 11-16mm T3 CINE Lens Review
- Tokina Cinema AT-X 16-28mm T/3 Lens Review
- Pentax DA* 60-250mm f/4 ED [IF] SDM Lens Review
- Pentax DA* 50-135mm f/2.8 ED [IF] SDM Review
- Panasonic Leica DG Summilux 15mm f/1.7 Review
- Voigtlander Nokton 58mm f/1.4 SL II Lens Review
- Voigtlander 40mm f/2 Ultron SL II Review
- Tamron 16-300mm f/3.5-6.3 Di II VC PZD Review
- Samyang 12mm f/2.0 NCS CS MFT Sample Photos