Most photographers buying big telephoto lenses are thinking about reaching out to relatively distant subjects. Conversely, folks wanting close-ups will often acquire a good macro lens. But don't forget that modern telephotos often focus pretty close, increasing their utility as "telephoto-macros". With its high magnification, a telephoto lens that can focus as close as about 2 or 3 meters can bring out intense detail in small nearby subjects. As an added bonus, skittish critters like dragonflies or butterflies will often tolerate slow approaches to 6 or 8 feet but flush if a lens is thrust any closer. So a telephoto can be perfect to photographically nab these gems. On those wonderful occasions when a wild bird is really close, this technique can also yield stunning portraits!
A few considerations for telephoto-macro photography:
- If you've never tried this technique, find a little target like a pebble or leaf and see how close you can get with your camera still able to focus. (If you have a focus-limiting switch don't forget to select the full range or near range, depending on the lens.)
- Telephoto lenses inherently yield very narrow Depth of Field (DOF). Even a smallish butterfly can have the body in focus but upturned wings out of focus. Solution: crank down your aperture (increase the f-stop.) To explore how DOF for your lens is dependent on variable distance and aperture, try a utility like Simple DoF.
- For longish subjects like dragonflies, it may be difficult to get the whole critter in focus if the body is angled away from the camera. Here you can make the artistic decision to just let the back go soft (focus on the eyes if in doubt.) If you want everything sharp you may need to reposition so the head and body are nearly perpendicular (and thus nearly equidistant) to the lens.
- Cranking up your f-stop will slow your shutter speed. If you've lost too much speed to get sharp images (especially if you are hand-holding the lens), bump up your ISO until you get satisfactory shutter speed back.
- Review your shots in the field by blowing up the image on your camera's display. Can you see bristles or tiny antenna on a dragonfly? Can you see scales on a butterfly wing? If not, keep trying. This is a pretty experimental, non-standard technique so figure out what works for you!!
Yours truly photographing odes stream side in Weld County, Colorado, July 2011. (Photo by John Barr.) While I'm using a big telephoto (Nikon 200-400mm f4 VR + 1.4X teleconverter), my subjects are within 10 feet of the lens. All photos below taken with this rig.
American Rubyspot, Weld County, Colorado, July 2011.
Pale Clubtail, Weld County, Colorado, July 2011.
Crab (genus Graspus? Help me out here if you know.) San Diego County, Colorado, October 2011. These guys would scuttle away when I tried my conventional macro but stayed put and continued feeding when I was 8 or so feet back using my telephoto-as-macro technique. I kept most of the 4" or-so wide critter in focus by dialing my aperture up to f/14.
Sometimes you don't want to get too close!! Black-tailed Rattlesnake, Santa Cruz County, Arizona, August 2006. Note the limited depth of field here- gives an artistic effect but leaves most of the snake out of focus. In these cases make sure the eye is sharp.
Sometimes a bird makes an especially close appearance. Stay tight and go for a portrait!! Sage Sparrow, Boulder County, Colorado, April 2010.