Using Close-Up Filters for Macro Photography
I often hearing people saying, “there’s nothing to photograph!” but what they usually mean is that there are no beautiful blue skies filled with puffy clouds or they’re not on the beach in Cancun. Heck, I wished I was in Mexico right now but if you take the time to look around there are great photographs just waiting to be captured. One of the least obvious photo ops is getting up close and personal with your subject and making macro images. And one of the best aspects of macro photography is that you can do it close to home.
The above image was captured at the Butterfly Pavilion in Westminster, Colorado using a Canon EOS 1D Mark II N and a MR-14EX ring lite in E-TTL mode. Exposure in Aperture Priority mode was 1/250 sec at f/16 at ISO 400. Places like this offer wonderful wintertime photo ops.
The classic definition of macro photography is that the image projected onto the digital sensor (or film plane) is the same size as the subject. At a 1:1 ratio, an SLR with a full-sized chip should have the ability to produce life-size magnification and focus on an area as small as 24×36 mm. Yet manufacturers sometimes describe a lens’s close-focusing capabilities as “macro” even if it doesn’t quite meet that definition and over time the term has gradually come to mean being able to focus on a subject close enough so the image is life-size or larger when viewing a 4×6 inch print. If you do the math, this only requires a magnification ratio of approximately 1:4.
Conventional wisdom is that close-up photography requires lots of expensive, specialized equipment and while it’s true that you can spend lots of money to make macro shots, you don’t have to break your piggy bank. Tiffen and other filter and camera manufacturers offer what is typically called close-up “filters.” Although not really filters in the traditional sense, they pass the duck test: They look like filters, work like filters and quack like filters, so I’ll call’em filters like everybody else.
Close-up filters are really supplementary lenses that use high-quality optics to shorten your camera lens’ close-focusing distance allowing you to get closer to the subject. Many close-up filters are available in different strengths (or diopters) as a set that includes versions labeled Close-up +1, Close-up +2, and Close-up +4. Close-up lenses are double-threaded so they can be used in combination with one another. Tip: to get the sharpest results it’s a good idea to place the strongest filter closest to the lens’s front element. For macro shooters on a budget, a complete set of close-up filters in 58mm threads should cost less than $40.
Factoid: Diopter is a unit of measurement that’s used to describe the power of a lens and is expressed as the reciprocal of the focal length in meters.