Part #2 of this Series picks up where Part #1 left off...and expands upon a few effective uses of electronic flash in macro photography.
Macro Photography
Tools and Techniques
Part #2
Fundamentals of Effective Lighting
Natural Light vs. Electronic Flash:
There is an on-going debate which is the more effective method to illuminate macro subjects in the field…natural light or flash. Most prefer natural light because "it’s there", and because...
"..It’s Natural."
A lesson soon learned in macro photography is that natural light, while more flattering to the subject, often proves to be the more problematic of the two options.
Understanding Mother Nature, and how her challenges relate to macro photography, represents the key to achieving higher quality imagery using natural light. In nature, there will almost always be variations of extremes. Bright sunlight can be exceptionally harsh. There will be distracting shadows which need to be filled with an alternative light source or a reflector. There will be hot spots reflecting off shiny surfaces which need to be softened to more acceptable levels with some type of diffusion material. There will also be instances when a photogenic subject is deeply shaded by an overhanging tree limb or other obstacle, necessitating longer shutter speeds and white-balance adjustments. (These and other natural light quandaries will be expanded upon in greater detail in a few “Field Challenges” later on.)
Sure, we all pray for that hazy, light-overcast sky…that naturally diffused “light box in the sky” which provides uniform illumination with minimal shadows. These ideal conditions (coupled with calm winds) are in every outdoor photographer’s dream. In Utopia, it makes perfect sense to capitalize upon the charitable gift from above and leave those flash heads in the car.
In virtually every other shooting situation though, it’s the wiser outdoor photographer who ventures into the field fully prepared for whatever Mother Nature may have in store that day. Packing one or two fully charged electronic flash units into the corner of one’s camera bag offers peace of mind. The decision to bring them along may even end up salvaging the day.
A NEWS FLASH
Electronic flash is versatile and controllable and represents a viable option every serious outdoor macro photographer should consider. In the beginning, I scorned electronic flash...mainly due to the fact that, like others, I was intimidated by it. Extensive field experience has helped to quell my fears and shed some light on how really effective those electronic flash units can be.
There are several styles and methods of flash illumination which can be utilized effectively in macro photography. The simplest type is the built-in, pop up flash head included on most modern film and digital SLR‘s. These tiny flash heads are generally weak and considered by many to be almost worthless during normal shooting scenarios. Fortunately, in most macro photography situations, our subject is less than a foot away. For such close encounters, the tiny, pop-up strobe can provide more than adequate illumination.
While a tripod is always recommended, the built-in flash can produce acceptable results while shooting hand-held with a true macro lens in the 105 to 200 mm range, either with or without extension tubes. (Trying to utilize the built-in flash with shorter length macro lenses, in the 60 mm range, may prove problematic. This is especially true when the lens is reversed or when extension tubes have been added. It will be difficult to fully illuminate the subject with the built-in flash at very close range, since a dark shadow will be cast over the subject due the light from the flash being partially shielded by the lens barrel.)
In most shooting scenarios, the key to success when shooting hand-held with any flash system is to select the fastest flash sync speed the camera will allow, preferably in the 1/200 to 1/250 second range. This will ensure that all motion, initiated by both by the subject and the photographer, will be frozen by the flash.
It’s also important to note that everything within range of the flash output will be recorded against a black background.
By dragging the shutter (...selecting a shutter speed which constitutes less time than the maximum flash sync speed), some ambient, background light will be allowed to record. This technique, which may also be described as “Slow Sync Mode”, can be tricky to implement but is extremely effective in creating more pleasing backgrounds when electronic flash is used as the primary illumination. While dragging the shutter helps to eliminate the black background associated with flash photography, it should only be attempted with a tripod-mounted camera and an immobile subject. When attempting this technique hand-held, or when trying to capture a subject which is moving around, there will be a strong possibility that ghosting will occur…meaning that all subject and/or camera movement occurring during the time the shutter remains open (both before and after the flash fires) will also record. The end result will be a discernible “halo” around the subject, or a fuzzy image…seemingly out of focus.
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In the above photos, it’s easy to see the inherent defects when attempting to use a slow-sync flash setting.
This emergent Oak Treehopper was photographed with a hand-held strobe at a shutter speed of 1/2 second. The flash was effective in freezing the bug's body, but a puff of wind during the half-second the shutter remained open created enough motion in the wings to cause a halo effect.
It’s also important to mention that attempting to use the built-in flash, or even a more powerful shoe-mounted strobe, with a bellows system will likely result in unwanted shadows forming in the bottom portion of the frame. This aberration will be caused by the limited direction of the light source during really close encounters. The visible shadow area will, as in the previous scenario, be the result of the light from the flash output coming into contact with the lens barrel.
To help combat this flash dilemma, there are a number of commercially made multi-flash brackets available which can be meticulously positioned to re-direct the light. The direction and intensity of several flash heads can be adjusted to fire simultaneously to provide even illumination directly toward the subject and help to fill in shadows.
There are two downsides to these versatile, multi-flash systems (aside from their cost). Too often, the arms of the bracket, or one of the flash heads, gets in the way and disturbs surrounding foliage…sending a skittish bug fleeing for cover.
They also tend to produce abnormal, multiple catch lights in the subjects eyes. Some overly fussy folks might consider these distracting, but they can easily be corrected in the digital darkroom.
Aside from that, those multi-flash systems come highly recommended.
There are also circularly designed flash heads which attach to the front of the lens barrel via an adjustable ring. Ring flash units are extremely effective tools for really close macro photography applications. They surround the subject with uniform illumination…even when only inches away.
As with the multi-flash systems, ring-flash units tend to produce abnormal catch lights, but they are barely noticeable and easily corrected.
Now that we've outlined some of the more common types of flash photography options available to the macro enthusiast, there’s a much simpler, but effective method to achieve high quality macro images with flash utilizing basic equipment…but with specialized techniques.
A shoe mountable strobe, which has wireless remote capabilities, can be hand-held in virtually any position to illuminate any macro subject. Being wireless, there are no pesky cables to get in the way.
All of the major camera manufacturers offer matching dedicated flash units which can be activated remotely. How they can be triggered into firing will vary. Some are designed to be activated by the built-in flash on the camera body, while other more advanced styles have their own dedicated, radio control or infra-red triggering systems.
(An old, inexpensive strobe you already own can also can be modified with an infra-red receiver, with a matching infra-red trigger attached to the hot shoe mount of the camera body.)
The primary advantage to this simple system is its versatility. Since the flash is hand-held, bracketing exposures becomes a breeze by simply holding the unit closer or farther away from the subject during subsequent exposures. It’s wise to select a flash unit which can be manually adjusted to varying power output levels. By selecting the lower power settings (1/4 or 1/16), re-cycle time becomes much faster. This allows the photographer a much quicker work flow when bracketing multiple frames of the same subject.
It’s also advisable to bracket not only the intensity, but also the direction of the light. This is easily accomplished by holding the flash closer, farther away, or at varying angles during subsequent exposures. Depending upon the subject, the flash head can often be positioned in such a way that the shadows fall completely out of the frame.
With a digital camera, it’s easy to observe the effect of each flash output and instantly make adjustments to the intensity and direction of the flash. Since dramatically different results can be achieved from the same shooting position by changing the direction of the flash, it’s wise to create different versions of the same scene. Each exposure can be later analyzed to separate the wheat from the chaff. Quite often, we end up liking several different exposures of the same subject. The only difference between them is the direction of the light.
As evident in these two intimate portraits of a rather handsome crane fly, bracketing the direction of the flash can afford the macro photographer the diversity to record several different renditions of the
same subject.
With practice, handling and positioning the flash will seem effortless and we can opt to implement other techniques, such as applying diffusers, flash filters or reflectors to augment and fine tune our flash exposures. This simple, hand-held flash technique pairs extremely well with a tripod mounted macro bellows system. Massive light loss, inherent with a stopped-down lens and fully extended bellows, will necessitate an effective flash position which may end up being mere inches away from the subject.
Mixed Lighting
During the previous discussion, we mentioned “dragging the shutter” during flash exposures to allow ambient light to also record. This represents a form of mixed lighting, indicating that two or more sources of illumination (…sometimes, representing different color temperatures) are utilized during a single exposure.
In practice, intentionally applying additional light sources can help add new life to our macro subjects.
Back in the day, film photographers needed a thorough understanding of color temperatures, especially when using slide films. These color temperatures (or suggested uses) were printed on the film box. To benefit digital camera users, approximate color temperature ranges typically encountered are included in the "White Balance Settings" section of the owners manual. Color temperatures are characterized using the Kelvin scale, and are listed as follows:
2700 K…Sodium Vapor-lamps (Typical light found within sports arenas.)
3000 K…Incandescent (Very Warm…Can be referred to as “Indoor Light”)
4200 K…Cool-white Fluorescent
5200 K…Direct Sunlight (Can also be referred to as “Daylight”)
5400 K…Electronic Flash (Similar to Daylight temperature)
6000 K…Cloudy (Moderately cool light…Typically occurring during daylight under overcast skies)
8000 K…Shade (Very cool…Occurs in deep shade on a sunny day)
Film camera users (especially slide film shooters) have to balance their film to their intended source of illumination, and have to accurately predict how their film’s emulsion will react. There’s no way for slide film users to see the end result until much later, when the processed slides come back from the lab and are sitting on the light table.
With modern digital cameras, it’s much simpler since we can examine each exposure at the scene and instantly make whatever adjustments needed to achieve our desired result.
Even in the Digital Age, some knowledge of color temperatures can be beneficial. Since our machines have been programmed so efficiently to “correct things” when we utilize their auto-features, we should feel comfortable when manually selecting appropriate white balance settings to match existing conditions. We should also be well aware of our intended outcome when additional light sources are applied to our scene.
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With the white balance set to Direct Sunlight (5200 K), the portion of the frame illuminated by sunlight will record nearly the same as seen by the naked eye. The light from the flashlight is warmer (around 2,700 to 3,000 K), so that portion of the frame will record with a an amber glow…similar to the light from a setting sun.
The miniature landscape above was photographed with outdoor balanced slide film (Provia 100). There were actually three light sources which came into play…all representing different color temperatures. The blurred waterfall in the background was partially shaded while the moss in the foreground was bathed in sunlight.
The light from a battery powered flashlight was positioned from the left side to create an amber glow on the mushroom caps.
Slide films seem to represent relevant color temperatures more accurately their digital counterparts, but a manual setting of 5200K on a digital SLR should yield similar results.
The flashlight can also be used to frame macro subjects with dramatic, back-lit halos of light, create catch-lights in our subjects eyes, or add auxiliary light to our subjects or backgrounds. We can be experimental and play with the light by covering the flashlight head with different colored filters and/or selecting varying white balance settings between exposures. The possibilities are limited only by our imagination. The practice and implementation of mixed-lighting techniques allows us to utilize our inner-visions to create in-camera, graphic imagery in which the photo’s primary point of interest is the light itself.
© Bob Cammarata 2015
bobcammarata.blogspot.com
(All photography by the author, except where noted. Thanks to Bill Vanko at VankoVision for the use of the photos.)
No portion of this material may be copied or used without permission
Go To Part 3 of this Series
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