|This Article Features Photo Zoom|
|Ice Crystals. Using manual changes in focus, nine images and Zerene Stacker software, Lepp rendered a completely sharp image of a translucent bladder seed pod frosted with feathery crystals on a cold, clear Oregon morning. Canon EOS 5D Mark III, EF 180mm macro lens, 1⁄125 sec. at ƒ/16, ISO 200.|
In my role as a Canon Explorer of Light, I recently presented a short, but intense seminar to the ASMP Student Chapter at the Brooks Institute of Photography in Santa Barbara, California. The event was especially interesting to me because I graduated from Brooks more than 40 years ago. It was a real treat to work with an SRO audience of young, fresh, enthusiastic, soon-to-be-pro photographers and their instructors.
Back in my student days, preparation for a career in nature photography wasn't part of the school's agenda; my instructors barely tolerated my sometimes outlandish efforts to incorporate my passion for nature into every assignment. So when I had these creative young people, my future fellow Brooks' alumni, in my clutches for an evening, I put together a program that featured my latest forays into extreme capture techniques as applied to nature and outdoor subjects. It really brought home to me the ways in which the huge technological advances of the last four decades have expanded my creative horizons. Here are some of the highlights from my presentation at Brooks.
Unlimited Depth of Field
For me, one of the most frustrating limitations of film photography was the inability to control and/or expand the areas of sharpness in an image. In the digital age, I use a variety of methods to achieve all the depth of field I want, where I want it.
These techniques are most revolutionary in macrophotography where a process called stacking—capturing the subject in a series of miniscule, precisely focused slices, then assembling the slices in post-capture software—is the way to defy physics and produce completely sharp images at magnifications far beyond life-size. In illustration of this technique, I wowed (and disgusted) my audience with a series of images of hideous, miniscule, dog parasites photographed at 10X and projected at wall-size in all their hairy, bloodsucking glory.
When working at magnifications of 1X or less, a photographer can make the sequential captures manually, either with integral adjustments in focus or the camera's position, but each slice of in-focus composition must overlap the next. This can result in many captures that, taken together, still achieve what seems like only a small amount of depth of field. But at high magnifications, depth of field is very limited—approximately 1.5mm at 1X with ƒ/11, and substantially less at higher magnifications. When I use the stacking technique for depth of field at higher magnifications, I employ a tool called the StackShot, available from www.cognisysinc.com. This focusing rail with a controllable step motor can move the camera from 1 micron to several inches per shot in a stacked image. I assemble the captures in Zerene Stacker (zerenesystems.com) or later versions of Adobe Photoshop (CS4 to the current CC) and Helicon Focus (heliconsoft.com.)
Stacking isn't only for macrophotography. I often use the technique for landscapes when the scene is beyond the capabilities of a single image at a small aperture. A typical composition would include important detail in the foreground, mid-range and distance, such as the iconic Arizona wildflower/cacti/mountain vistas David Muench captures with his 4x5 view camera. Now you can achieve this with your 35mm DSLR. Mounting the camera on a tripod is necessary to keep all the images in register as you manually rotate the focus ring on the lens to break the composition into numerous overlapping slices of in-focus sharpness. It can require as few as two, or many, images to cover the full distance within the framed scene. Finishing the image using stacking software will produce a sharp image from foreground to infinity.
Back in the "good old days" of film, I captured lots of panoramas. The best I could do with them then was to make several prints and cut and paste them together to convey the entire scene. Years, sometimes decades, later, I resurrected those files, scanned the slides and assembled the panoramas in Photoshop. I still do that with traditional composite panos, but with much better quality and modern printers enabling high-resolution prints of 25 feet or more in size. Three of my favorite new panorama techniques are gifts of the digital age.
Aerial panoramas require a couple of extra tools: a plane and pilot. The pilot maneuvers the plane in a path that's parallel to the subject (say, a mountain range or shoreline); the photographer, optimally shooting from an open door or a window, captures a series of images at regular intervals timed so that each image overlaps the previous capture by about 50%. The result is a long panorama that comes together with the help of layer masks and some Photoshop skill, but there are many variables. The best software to stitch this type of panorama is Autopano Giga, a very powerful program from www.kolor.com.
Action-sequence panoramas are one of my favorite new techniques for wildlife photography, but I wish I'd had the chance to capture them when I was photographing Cobras and Cougars and Stingrays for Car & Driver magazine back in the '70s and '80s. The action-sequence pano portrays a subject's movement through time and space with a series of still captures taken along a vertical or horizontal path, then assembled into a panorama. Great subjects for this technique include agility dogs jumping several hurdles, human runners or dancers, flying birds or horses in competition, for just a few examples. If it moves in one direction and the background is interesting and not distracting, it will probably make a good action-sequence panorama. The keys to success here are to lock onto the subject as it moves, keep the horizon steady so the background will match up, and fire the camera at regular intervals, meaning let it rip. Use a large JPEG format rather than RAW to keep the files smaller and eliminate random pauses due to a filled buffer. When you compose the panorama, using Adobe Photoshop and layer masks, you probably won't use every image, but rather every second or third capture. For more information about this technique, see our article "Action-Sequence Panoramas," OP, January/February 2012.
The GigaPan HDR Or Stacked Combo. In my continuing quest for the biggest, sharpest, most detailed and dynamic images possible, I've lately expanded my use of the innovative GigaPan system (gigapan.com). The GigaPan is essentially a capture controller to which your camera/lens combination mounts; it captures a series of images in rows and columns within the frame and according to the instructions you've programmed. I use it for vast landscapes and for macrophotography with a 180mm macro lens and 2X tele-extender (360mm). It gets a little complicated when I want to achieve expanded tonal range in my GigaPan images; then I program the system to make a number of captures at different exposures. For expanded depth of field, I can stop the GigaPan in each position and manually obtain a series of refocused images that I later stack, then composite as a high-resolution GigaPan.
Extending Long Lenses
When photographing wildlife, longer is better—safer for the subjects, safer for the photographer. Using tele-extenders to multiply focal length has long been an option; while adding an extender to a telephoto lens degrades the image slightly, it's really camera/lens vibration, missed focus and atmospheric factors that are the big culprits when shooting with lots of glass.
For my Brooks audience, I shared a recent project where, over a three-month period, I photographed an eagle nest from 200 feet away, regularly using focal lengths of up to 3200mm (a Canon EF 800mm ƒ/5.6L telephoto lens with two 2X tele-extenders coupled with an extension tube) for both stills and video. I eliminated virtually all camera/lens vibration by using a quality tripod kept low and out of the wind, locking up the camera mirror (Live View) and, available with my Canon DSLRs, using the Silent Mode to eliminate all shutter motion, I used the CamRanger wireless transmitter to manage all of the framing, exposure, critical focus and capture functions, including switching from stills to video, from my iPad, without touching the camera at all. The resulting captures are of excellent quality, sufficient to grace the cover of this magazine or to generate generously sized prints.
Back To The Future
These are just a few of the techniques that I discussed with the Brooks Institute students; I hope I gave them some ideas to think about and apply to their favorite subjects. But just for a while, because at some point in the near future I'm sure these "new" techniques will be as old-fashioned to my young colleagues as my early efforts to overcome the limits of film photography seem to me now. I loved being back at Brooks and being reminded that I live in an exciting era of photography where there are few limits. But I really want to know what these young people will know, 40 years from now. I'm not sure how I'm going to bring that one off.
Follow George Lepp's exploits, see his latest photographs and be part of the discussion on his Facebook page: www.facebook.com/georgelepp.