Depth of field - Wikipedia
This Depth of Field (DoF) calculator will help you get the creative control on the design of your photos. Decide the zone of sharpness you need to tell the story. Understanding depth of field is one of the first big hurdles in photography. Wide or large apertures correspond with the small f-stop numbers. Depth of field is determined by three factors – aperture size, distance from the has a manual with a DOF chart for each f/stop and the major focusing distances.
Other than lighting, composition and focus which includes depth of field are the main elements that you can exercise complete command over.
The first thing to understand about focus is depth of field. As soon as an object person, thing falls out of this range, it begins to lose focus at an accelerating degree the farther out of the zone it falls; e. Shallow is when the included focus range is very narrow, a few inches to several feet. Deep is when the included range is a couple of yards to infinity. In both cases DOF is measured in front of the focus point and behind the focus point. DOF is determined by three factors — aperture size, distance from the lens, and the focal length of the lens.
Understanding depth of field is one of the first big hurdles in photography.
Understanding Depth of Field for Beginners
Knowing how your aperturefocal length and focusing work together to affect depth of field and control what appears sharp in your photos will give you incredible confidence as a photographer. What is depth of field?Understanding F-Stop and Depth of Field
A camera can only focus its lens at a single point, but there will be an area that stretches in front of and behind this focus point that still appears sharp. This zone is known as the depth of field. It's not a fixed distance, it changes in size and can be described as either 'shallow' where only a narrow zone appears sharp or deep where more of the picture appears sharp.
Because depth of field has an impact on both the aesthetic and technical quality of a picture. Sometimes you'll want to use an extensive depth of field in order to keep everything sharp.
A classic example is when you're photographing a landscape, where generally the most desirable outcome is to capture detail from the foreground to the horizon.
Other times, a shallow depth of field will be preferable. It enables you to blur background and foreground details, causing distractions to melt away and allowing you to direct viewers to the focal point in a picture.
Okay, so where do I find the depth of field control on my camera? Many digital cameras come with a Depth of Field Preview button near the lens mount, or enable you to assign the same function to one of the other buttons. However, this doesn't have any effect on the depth of field.
The image you normally see through the viewfinder or on the Live View screen is displayed at the lens's maximum, or widest, aperture; the aperture you dial in on the camera body will only be set when you take a picture. However, pressing the Depth of Field Preview button allows you to view the scene at the working aperture, so that you can see what areas will appear sharp. The depth-of-field scale top indicates that a subject which is anywhere between 1 and 2 meters in front of the camera will be rendered acceptably sharp.
Out-of-focus highlights have the shape of the lens aperture. Several other factors, such as subject matter, movement, camera-to-subject distance, lens focal lengthselected lens f-numberformat sizeand circle of confusion criteria also influence when a given defocus becomes noticeable.
Focusing Basics | Aperture and Depth of Field
For a given f-number, increasing the magnification, either by moving closer to the subject or using a lens of greater focal length, decreases the DOF; decreasing magnification increases DOF. For a given subject magnification, increasing the f-number decreasing the aperture diameter increases the DOF; decreasing f-number decreases DOF.
- Depth of field
If the original image is enlarged to make the final image, the circle of confusion in the original image must be smaller than that in the final image by the ratio of enlargement. Cropping an image and enlarging to the same size final image as an uncropped image taken under the same conditions is equivalent to using a smaller format under the same conditions, so the cropped image has less DOF.
Stroebel, — When focus is set to the hyperfocal distancethe DOF extends from half the hyperfocal distance to infinity, and the DOF is the largest possible for a given f-number. Relationship of DOF to format size[ edit ] The comparative DOFs of two different image sensor format sizes depend on the conditions of the comparison.
The DOF for the smaller format can be either more than or less than that for the larger format. In the discussion that follows, it is assumed that the final images from both formats are the same size, are viewed from the same distance, and are judged with the same circle of confusion criterion.
Understanding Depth of Field for Beginners
Derivations of the effects of format size are given under Derivation of the DOF formulae. Though commonly used when comparing formats, the approximation is valid only when the subject distance is large in comparison with the focal length of the larger format and small in comparison with the hyperfocal distance of the smaller format. Moreover, the larger the format size, the longer a lens will need to be to capture the same framing as a smaller format.
Conversely, using the same focal length lens with each of these formats will yield a progressively wider image as the film format gets larger: Therefore, because the larger formats require longer lenses than the smaller ones, they will accordingly have a smaller depth of field. Compensations in exposure, framing, or subject distance need to be made in order to make one format look like it was filmed in another format.
Same focal length for both formats[ edit ] Many small-format digital SLR camera systems allow using many of the same lenses on both full-frame and "cropped format" cameras.
If, for the same focal length setting, the subject distance is adjusted to provide the same field of view at the subject, at the same f-number and final-image size, the smaller format has greater DOF, as with the "same picture" comparison above.
If pictures are taken from the same distance using the same f-number, same focal length, and the final images are the same size, the smaller format has less DOF. If pictures taken from the same subject distance using the same focal length, are given the same enlargement, both final images will have the same DOF. The pictures from the two formats will differ because of the different angles of view. If the larger format is cropped to the captured area of the smaller format, the final images will have the same angle of view, have been given the same enlargement, and have the same DOF.
For a given DOF and field of view, the required f-number is proportional to the format size. The longer exposure time with the larger camera might result in motion blurespecially with windy conditions, a moving subject, or an unsteady camera.