Sunday, December 27, 2009

Understand Depth of Field or DOF

There are many things to know and understand when it comes to photography. Depth of field, Aperture, Shutter, ISO/ASA, basic lens knowledge, camera choice, computers, software, memory cards, and most important composition, rules of thirds and shooting for certain situations.

Definitions (both by Wikipedia and in layman’s’ terms)

Depth of Field:

In optics particularly as it relates to film and photographythe depth of field (DOF) is the portion of a scene that appears sharp in the image. Although a lens can precisely focus at only one distance, the decrease in sharpness is gradual on either side of the focused distance, so that within the DOF, the unsharpness is imperceptible under normal viewing conditions.

This is affected by the aperture, lens and focus point. For example to have overall sharpness, having a large depth of field is needed. Setting the camera at an F-stop (aperture) of F11 or F16 is going to produce the greatest sharpness from front to back of the image. Setting a camera at an F-stop (aperture) of F2.8 or F4 will produce a very shallow depth of field. This great for portraits, or other object where you want the background to be blurry; I shot football at F2.8/F4 for every game, this made the players pop, separating them from the background.

Football example:

Understanding and controlling depth of field allows for creativity and flexibility in your images. Most SLR/DSLR cameras have a DOF preview button or will allow you to assign a button to control this option.

Shallow Depth of Field Example:

Large Depth of Field Example:

Both of these examples give you an idea of creative ways to capture images using depth of field as a main influence in your image. This is a very basic understanding of depth of field. I suggest trying it out. If you have not already done so, take your camera out of the Auto mode (usually indicated by the Green Icon) and put it in aperture priority on your camera (mode or dial options; indicated as an “A” on Nikon and a “Av” on Canon. Shoot in aperture priority, shoot from the largest aperture which is at least F1.2 to the smallest aperture which is at least F32 (this will be explained in the next blog)

…more to come

No comments:

Post a Comment