There have been many recent posts by people considering venturing into the world of macro-photography. These posts occur frequently on the forums and usually start with “cheap’ ways to get into macro shots: extension tubes vs close up lenses; then progress to comparing Canon, Sigma, and Tamron macro lenses (they are all good optically), working distances vis-à-vis 50, 100, & 180mm; and eventually on to discussing light sources.
While not claiming to be an expert, or even a great macro photographer, I thought I would add my two cents worth on the illumination/aperture/shutter speed issues. (Actually given the length, you may be getting four cents worth.)
Whether an external light source is necessary for macro shots is really determined by the subject matter and how you wish to portray it. There are certainly plenty of good macro images out there that were taken using natural light. However, having some control of the light source can expand the range of macro opportunities.
Most macro shots require a lot of light. Unfortunately when natural light is at its brightest, full sun at midday, the conditions are hardly optimal because of high contrast and deep shadows.
For most outdoor macro shots, a combination of small aperture and relatively high shutter speed is required. Also, since you are dealing with images where a lot of detail must be preserved, an ISO of 400 or less is usually required.
Small aperture
For subjects that are to be shot at or around 1:1 the depth of field can is paper thin and apertures of f/16 or greater are often required. Apertures smaller than f/16 tend to cause diffraction problems and a loss of resolution – but there are times when depth of field is more important than resolution and f/22 or even f/32 must be used.
Relatively high shutter speed
At high magnifications (at or around 1:1) avoiding camera shake is a real problem. For macro shots, the magnification matters more than the focal length – a 50mm lens is no easier to handhold than a 100mm lens, if they are both at 1:1.
A tripod can help, but ...
You may think that a tripod would be a solution to the shutter speed problem, but live things tend to move around and dead things aren’t that interesting, and flowers can sway in the slightest breeze. Often, even with a tripod, slow shutter speeds are not desirable. Flowers, however are rarely true macro, but more usually just close ups.
With flash units, small apertures can be used with shutter speeds up to the sync speed of 1/200 or 1/250s.
Dedicated macro flash units, ring or twin lights, are a good way to provide external lighting. But they are an expensive solution and don’t have many ancillary uses. The camera’s built-in flash can be used, but diffusing the flash is a problem, and because of the direction of the output, much of the light passes over and not on to the subject. I have, however, seen many good macro shots using the built-in flash for fill.
Flash units such as the Canon 420ex, 550ex, and 580ex can be used very successfully, especially when used with a diffuser such as a Stofen Omnibounce or Lumiquest Softbox. These units can be mounted in the hot shoe, or when used with an off camera cord, held beside the camera or mounted on a bracket. Units like the 550ex can be tilted down 7° to help alleviate the directional problems of hot shoe mounting. If your camera does not have FEC, the 550ex and 580ex flashes are better choices than the 420ex or built-in flash.
For insects and other fauna I use a 550ex, shoe mounted with a Omnibounce. I use apertures in the f/11 – f/16 range and shutter speeds in the 1/125 – 1/160s range. I rarely use f/22 and 1/200s because I want some ambient light in the shot – using very small apertures and fast shutter speeds leads to black backgrounds, which I generally do not like. Some photographs prefer black backgrounds because they isolate the subject, but I find they give a very artificial quality to the image.
For flora I sometimes use natural light with a collapsible reflector. At other times I use one or two 550EXs with diffusers – often with the camera on a tripod and a 550ex handheld. In woods and other low light situations I use both 550EXs, generally mounted on cheap, lightweight tripods and use a shoe mounted ST-E2 remote trigger to fire them.
All the best,
Brian A.
While not claiming to be an expert, or even a great macro photographer, I thought I would add my two cents worth on the illumination/aperture/shutter speed issues. (Actually given the length, you may be getting four cents worth.)
Whether an external light source is necessary for macro shots is really determined by the subject matter and how you wish to portray it. There are certainly plenty of good macro images out there that were taken using natural light. However, having some control of the light source can expand the range of macro opportunities.
Most macro shots require a lot of light. Unfortunately when natural light is at its brightest, full sun at midday, the conditions are hardly optimal because of high contrast and deep shadows.
For most outdoor macro shots, a combination of small aperture and relatively high shutter speed is required. Also, since you are dealing with images where a lot of detail must be preserved, an ISO of 400 or less is usually required.
Small aperture
For subjects that are to be shot at or around 1:1 the depth of field can is paper thin and apertures of f/16 or greater are often required. Apertures smaller than f/16 tend to cause diffraction problems and a loss of resolution – but there are times when depth of field is more important than resolution and f/22 or even f/32 must be used.
Relatively high shutter speed
At high magnifications (at or around 1:1) avoiding camera shake is a real problem. For macro shots, the magnification matters more than the focal length – a 50mm lens is no easier to handhold than a 100mm lens, if they are both at 1:1.
A tripod can help, but ...
You may think that a tripod would be a solution to the shutter speed problem, but live things tend to move around and dead things aren’t that interesting, and flowers can sway in the slightest breeze. Often, even with a tripod, slow shutter speeds are not desirable. Flowers, however are rarely true macro, but more usually just close ups.
With flash units, small apertures can be used with shutter speeds up to the sync speed of 1/200 or 1/250s.
Dedicated macro flash units, ring or twin lights, are a good way to provide external lighting. But they are an expensive solution and don’t have many ancillary uses. The camera’s built-in flash can be used, but diffusing the flash is a problem, and because of the direction of the output, much of the light passes over and not on to the subject. I have, however, seen many good macro shots using the built-in flash for fill.
Flash units such as the Canon 420ex, 550ex, and 580ex can be used very successfully, especially when used with a diffuser such as a Stofen Omnibounce or Lumiquest Softbox. These units can be mounted in the hot shoe, or when used with an off camera cord, held beside the camera or mounted on a bracket. Units like the 550ex can be tilted down 7° to help alleviate the directional problems of hot shoe mounting. If your camera does not have FEC, the 550ex and 580ex flashes are better choices than the 420ex or built-in flash.
For insects and other fauna I use a 550ex, shoe mounted with a Omnibounce. I use apertures in the f/11 – f/16 range and shutter speeds in the 1/125 – 1/160s range. I rarely use f/22 and 1/200s because I want some ambient light in the shot – using very small apertures and fast shutter speeds leads to black backgrounds, which I generally do not like. Some photographs prefer black backgrounds because they isolate the subject, but I find they give a very artificial quality to the image.
For flora I sometimes use natural light with a collapsible reflector. At other times I use one or two 550EXs with diffusers – often with the camera on a tripod and a 550ex handheld. In woods and other low light situations I use both 550EXs, generally mounted on cheap, lightweight tripods and use a shoe mounted ST-E2 remote trigger to fire them.
All the best,
Brian A.