Want to create studio-quality macro images of wild subjects in their environments? Try these tips to build a macro field studio for photos on location
the work of Richard Avedon, Jim Balog, Susan Middleton and David Liittschwager, we see the power of a simple white background, whether the subject is human or animal. Without the distraction of a background, we can concentrate on the appearance of the subject, which creates its own composition within the limits of the frame. In animal and plant photography, without the context provided by a background, the subject becomes an individual rather than the member of a species or community. It’s an approach that personalizes. And it makes for very striking images.
Field studio photography — and all of this work is done in the field rather than indoors—frees the photographer from the tyranny of bad light. Strobe light means you can be productive even if the conditions would see you give up on a regular macro shot. And if you’re trying to fit your photography in around other responsibilities, that’s a boon. The approach also allows you to revisit subjects you have shot many times before but to present them in an entirely different way and with an unparalleled degree of clarity.
The Twist: Backlight
Shooting on white is nothing new, but the twist we bring is to backlight the white background. By doing this, the translucent qualities of the subject are shown, introducing a depth that is absent in cut-outs or front-lit photographs; it glows.
In field studio work, we’re also scrupulous about how we work with subjects in the field. Plants are photographed in-situ; animals introduced into the set or tank remain there for only a short time before being returned to the spot they were found.
What You’ll Need For A Macro Field Studio
This technique calls for minimal investment to get started, and the results from very simple gear are pretty much indistinguishable from those from a high-end set-up. More money buys more convenience, but not quality.
I’d recommend you learn the technique on plants before applying the principles to more active subjects. So, in addition to your normal macro gear, you will need:
- Two strobes with controllable output, one for lighting the background and one for front-fill.
- A radio trigger that allows both strobes to be synchronized off-camera.
- A piece of translucent ⅛-inch white Plexiglass with a light transmission rating of about 40 percent, at least 15×18 inches in size (this acts as the background).
- A piece of translucent corrugated plastic sheet around 15×15 inches (this diffuses the front light).
Clamps and supports for the background and lights are very helpful too, but not vital at this stage.
Key Principles Of A Macro Field Studio
When we talk about a “pure white background,” what we mean is one that is blown in all three channels: R255, G255, B255. There are two main reasons we want this. As I’ve already mentioned, a bright backlit background will make any translucent parts of a subject glow. But there are also implications for what we can do with the photograph after. If the background is pure white, it makes the matter of compositing several images together on a page — perhaps to illustrate biodiversity — a breeze. If you have tried to cut out an out-of-focus edge, you know how hard it is to do convincingly, especially if the edge is very complex (as you often find with insects). But if the subject has been shot on a pure white background in the first place, you can make a loose selection well away from its edges and drop it seamlessly onto a white page.
In this work, it’s important to understand the principle of “forward light spill.” If you create a pure white background, it’s pure white whether it is 5 inches or 5 feet behind the subject. Its inherent whiteness doesn’t change. But what does change is how much light spills forward from the background onto the subject. The closer it is, the more translucence is shown, but the risk of overwhelming the subject, of light wrapping around the edges of it in an unattractive way, is greater, too. As the background is moved further back, so the backlighting effect is diminished, but edges of the subject are likely to be better defined and less at risk of blending with the background if they are light. So, the principle is simple: for dark or opaque subjects, have the background close; for pale or translucent ones, have it further away. Thus, by managing distance and front light, it’s quite feasible to photograph white subjects on a white background, with intriguing results.
If you’re working with plants, it’s as simple as moving the background closer or further away. With subjects that need to be contained, however, you can’t simply set them directly onto a white background, for the reasons above, so instead I use a transparent set that allows me to manage the subject’s distance from the background.
One final point concerning the front light. The universal principle that a large light close to the subject gives softer shadows than a small one further away is relevant here. Soft front fill is the most sympathetic type of light for field studio work, hence the large front diffuser sheet. The front strobe should be held far enough behind the sheet to light it all. Ring flashes and similar set-ups that hold the flash close to the axis of the lens aren’t suitable for this work.
Getting The Exposure Right
Your camera’s histogram and highlight warning are your best allies when it comes to working out the right exposure. You should have values recorded on at least two-thirds of the histogram; if there is nothing in the left half, then the picture will be too light.
- Set the camera to shoot RAW and the exposure mode on the camera and flash to Manual. No Auto ISO, please.
- Select a low ISO, perhaps 320, ƒ/16 and your camera’s highest flash sync speed for manual units (1/200 second in my case).
- Set the background flash to about ½ power and, with the front flash out of the way, take a test exposure. Do this by firing the flash from behind the background Plexiglass, far enough from it to light the whole sheet. The background should all be over-exposed (blinking on the back of the camera if highlight warnings are enabled) — but only just. Keep reducing the power until it is no longer overexposed, then increase again until it is, and no more.
- Swing the front flash into position without changing any of the existing settings, and make a test exposure. Adjust the flash’s output as needed for more or less front light or, if you can’t adjust it independently of the background flash, alter its distance from the subject until the front exposure is good, too. That equates to not overwhelming the backlight effect.
- It should be necessary now to make only small adjustments as you shoot at different magnifications.
If the corners of your image aren’t as white as they should be, it may be because the pool of light thrown by your flash isn’t quite big enough. Either pull it back a little or simply crop out the corners during processing.
Working Principles For Field Studio Photography
There is a bit more gear involved in this sort of photography compared to other macro work. I tend only to photograph isolated plants or those on the edge of colonies. Rather than cut vegetation that’s getting in the way, I hold it aside with small sheets of lightweight corrugated plastic held down with pebbles. If you are working with animals, set up in the shade and work out exposure before introducing any subjects to keep their time “on set” to a minimum.