Text and images by: Todd Winner
Between Facebook, Instagram, Flicker and all the other social outlets the average person looks at hundreds of images every day. So how can you make your images stand out from the crowd? One way is to use shallow depth of field. Our eyes naturally move to the area of sharpest focus, so by isolating your subject against a beautifully blurred background it directs your viewer to the important part of the image. Your subject won’t have to compete against a busy background that is equally as sharp.
For underwater photographers this is going to be most easily achieved using our macro lenses. The super wide lenses we typically use underwater for wide angle have too much DOF, even wide open. There are a number of factors that affect depth of field but some of the more important ones to consider are sensor size, focal length, subject distance and aperture. Larger sensors, like those found in full frame cameras, have much less DOF than the small sensors found in most compacts. Longer focal length lenses have less DOF than shorter focal lengths. Moving closer to your subject or anything that adds magnification, like adding a wet diopter, will give you less DOF. Wide apertures or f–numbers like f/2.8 have shallow focus while narrow stops like f/22 have deep focus.
Be aware of objects that may still be visible in the foreground of the frame. Because we are working with very narrow depth of field, if these objects are closer to the lens than the subject, they will also be out of focus. Out of focus foregrounds can be distracting, but used intentionally you can create some interesting images.
I can’t stress how important it is to check your focus. With very shallow DOF it may be impossible to to have both eyes or rhinophores in focus. Typically you want to focus on the eye that is closest to the camera. Because the plane of focus is perpendicular to the lens, how you angle the camera will have a big impact on what is and is not in focus. So in practice get close, open up your aperture and nail focus!
Todd Winner is a contributor, instructor, and trip leader for Samy’s Underwater Photo & Video and has over 20 years of experience in underwater still and broadcast video. To see more of Todd’s work please go to www.toddwinner.com. For the latest information on workshops and trips, sign up for .our newsletter