One Flash Photography part II
I have tendency to forget my boots. And shoes. Anyone who has spent time with me in the field outside of workshops (thank god I always remember them on workshops) can attest to this. It’s not that I don’t have the boots with me. It’s that I forget to put them on and leave them elsewhere. So, I end up places with flipflops or sandals or barefooted. It’s one of my more endearing qualities. I like to tell myself this means that deep down I’m really a genius. As luck would have it, I at least managed to stumble out of the little AirB&B I was renting with flipflops on this morning.
Somehow, I managed to end up with a thorn filled vine between my foot and flipflop, and as I stepped forward I dragged the soul of my foot down the entire length of the vine. Looking down, my otherwise brown flipflop was red with blood. And naturally, that’s when I noticed the pitcher plant right beside my foot with a little frog staring up at me. The foot can wait.
Backing off the bramble that was in my flipflop, I moved slowly now so as not to scare my subject. I laid my pack on the ground and set down beside it, closely watching the frog closely watch me. Getting eye to eye with a little frog like this something we should all do more of in life.
Sizing up my little pine woods tree frog and its surrounding environment, I realized there was a number of different shots that could be made here with flash. This is the beauty bringing your own light source into the wild. It gives us creative control over our compositions. Once we begin to manage the light ourselves, all sorts of creative opportunities become available to us that we might not have otherwise.
The first thing you need to understand about using flash is that you are working with two different exposures at the exact same time. One exposure is set in your camera. The other is set in the flash. If you can come to terms with this, then you are well on your way to making magic in the field.
First, the camera itself.
In camera, you want to set your exposure for the ambient light of the composition. If you have read anything about using flash before, then you probably know this much at least. But, what does it really mean?
For our purposes, it’s easiest to think of the ambient light in terms of how you want the background to look in the final picture. Do you want a mid-tone background? Do you want a bright background? Do you want a dark background? Naturally, the more light we allow into the camera, the more obvious the background is going to be as well. Thus, if you are setting up a composition to actually show detail in the background for context, then you want to make sure you set an exposure with enough light to do just that. What to do with the background should never be taken lightly. This part is crucially important as it ultimately dictates so much about the overall look and feel of the photograph you want to create.
The camera’s exposure always come first. Because the camera settings are all about the ambient light and background, this sets the stage for the rest of the photograph. It’s not unlike painting in that you build your composition in layers.
Next comes the flash, and here you have two options: manual and TTL. Manual is pretty straight forward. You dial in the exact amount of flash that you want. These setting are represented in fractions such as 1/32 or ½, with 1/1 – which represents full power. You should know that this actually has nothing to do with the intensity of the light, however. 1/32 vs 1/1 does not change how much light the flash emits. Instead, it changes the duration of the flash.
Manual flash is best used when your lens and flash unit are absolutely positively not going to change distance from the subject. In other words, I only use manual if I’m shooting from a tripod. If I am hand holding, if I am moving around, then its 100% TTL for me. And when it comes to macro photography, such as working with my frog and pitcher plant, moving just a couple inches can change everything.
The reason that I prefer to shoot in TTL, unless I am attached to a tripod and can ensure the distance won’t change, is because of an obnoxiously titled thing called the inverse square law. This is physics. It governs how light falls off. Logic would suggest that if you double your distance from your subject, you should double the flash exposure to compensate. But this is not how light works. Instead, you would need to quadruple the exposure – which means you also need to know your distance to begin with.
The inverse square law of light states that the intensity of light is inversely proportional to the square of the distance.
I am not going to do the math in the field. It’s simply not going to happen. We have a hard-enough time getting all the other elements to come together here, and as my flash moves in distance from my subject, I am not going to work out an equation to reset my flash exposure. Especially when I’m lying in some ridiculous yoga position, in the mud, with mosquitoes flying up my nose, sweat dripping into my eyes, blood leaking from the soul of my foot, and trying to handhold a Nikon D5 with lens and flash bracket and flash extender and, well, you get the point. Blood, sweat, and math? Nope.
And so this is where TTL comes into play, which stands for Through The Lens.
Don’t confuse this with your TTL light meter. This is different. Whereas your TTL light meter (yes, you have one) is looking at light, the TTL setting on your flash is judging distance. When you are in TTL mode, you flash fires a quick burst of “pre-flashes” at the subject. The light bounces off your subject and back to the camera which then determines the distance of the subject from the camera sensor and your flash makes adjustments accordingly. All of this happens in a blink of the eye. It’s super-fast and quite amazing when you think of the computations that are happening here almost instantly for you.
With TTL, we no longer set things manually in fractions. Instead, we use FEV or FEC depending on if your Canon or Nikon. Both mean the same thing really, and that is Flash Exposure Compensation.
This is like shooting in aperture priority and adjusting for the light with exposure compensation. You will recognize the settings as they move in 1/3rd increments. This means you might dial in a FEC of -1.7 or +2 for instance.
TTL is taking distance readings between your subject and flash and constantly adjusting the flash output accordingly, doing all the math for you. FEV is then saying you want more or less flash depending upon your own creative interpretation of the situation. In other words, it makes life a whole lot simpler when you’re in the field, when we are shooting in the wild.
As fantastic as TTL sounds, there is one small caveat: it robs you of a bit of your flash power / duration. Since the flash is sending out a quick pulse of light just before the shutter is triggered, you lose a little something in the process. In most instances, this is irrelevant. However, there are some scenarios, such as when trying to fill in harsh shadows in bright conditions, where you may need every bit of flash your little unit can muster up to compete with the ambient light. But, let it suffice to say that you will find my flash unit set in TTL mode 99.9% of the time when I’m in the field.
Sitting down in the wiregrass, I try my best not to crush the Venus flytraps that I see randomly about with mouths opened towards the heavens. I’m eye level with this frog, which is where I always prefer to begin with any wildlife subject. The background is a bit cluttered for my taste, but this is easily overcome with the use of a 105mm macro lens. This lens just barely inches its way into the telephoto category, and thus I can count on my perspective being compressed enough to help blur out the background – if I so choose to even let the background remain in the photograph to begin with of course. This, along with shallow depths of field give me plenty of control over the type of background that I want to create here.
Before I ever begin photographing, I am analyzing my background. This isn’t just in macro or flash photography either. This is in everything. Whether I am photographing a brown bear in Alaska or poison dart frog on the coast of Panama, background comes first. Well, really light and background come first. But in this instance, I’m using flash and so I can control the light.
“The closer your flash is to your subject, the less contrast you will create and the softer the transition from highlights to shadows, e.g. the more natural looking the image will be. ”
Given the fact that I’m not working in overcast conditions, and there is quite a bit of ambient light to contend with, I have my camera and flash set to High Speed Sync. This is important. You see, your flash can only sync at shutter speeds up to 1/250th of a second. There is a little variation here between camera bodies and manufacturers but most cameras top out at 1/250th of a second.
The reason for this is that with a single burst of flash you will end up with a black bar across your photograph thanks to your shutter. The shutter in your camera is not a single object that moves up and down when you trip the shutter button. Instead, it opens and closes in layers. And it is one of these layers that ends up getting in the way.
With High Speed Sync turned on, you can crank your shutter speed up as high as you need to for the most part. Similar to the pulse of light that occurs when you are set up in TTL mode, High Speed Sync (HSS) causes the flash to send out a burst of flash instead of a single pop. This burst helps to fill in the gaps created by the various shutter curtains.
All of this works to allow me to use a faster shutter speed for controlling the ambient light. It also allows me to work with larger apertures (less depth of field). Without HHS, there is a good chance that I just would not be able to balance the camera and flash exposure properly in these brighter conditions. Otherwise, I would end up overexposing the photograph.
My pinewoods treefrog is more than cooperative. Not only was it so kind as to actually be visible outside of the pitcher plant, it is mellow enough to allow me to get down and move in close. I take my time of course, moving slowly, methodically, as I inch into place. All the while my frog just stares at me. And I stare back.
Anytime I am working with a relatively cooperative subject like this, I try to create as many different types of photographs as I can. I know exactly the type of photograph I really want to create here, but I’m also in the business of selling photographs to magazines – who all tend to have different tastes. Thus, I tend to start mild and build up to spicy. When it comes to something like this frog in a pitcher plant, where I have the capability of using off camera flash, starting mild means creating something of a balanced lighting ratio. Doing this means that I simply increase my in-camera exposure for ambient light and I pull my flash back from the subject to soften the edges of shadows.
Even with a goal to create a balanced exposure between the flash and the background, I opt to keep my background a little on the darker side. This is not to say completely black. But it does mean that I want the background to be a touch darker than midtone.
The reason I do this is to make my subject pop. Even when trying to create the most even light for the composition, you still want your subject to stand out from the rest of the photograph. And a light subject against even a slightly darker background will stand out with a touch of drama.
If not for my flash bracket and telescoping flash extender, I would be stuck with a flash that is stuck on the hot shoe. This would be limiting in every way imaginable. I could only have the light source coming straight on at my subject. There would be no creativity here. I would only be able to use fill flash, and I would fight with myself to keep shadows.
When it comes to using flash, shadows are your friend. You want shadows of some sort. Shadows are a natural part of life. Very rarely do we not find at least some amount of shadow everywhere we look. Thus, when using flash, at all times you want to make sure that you have some amount of shadow – either from natural light or from the flash unit itself.
The two photographs above are, of course, not from the longleaf pine savannah. Both of these images were created in Central America. I included these photos, however, to show that even with a single flash, you can still create different styles of lighting. Often when wildlife photographers work with one off-camera flash, they create a chiaroscuro style image such as the eyelash viper. But you are not limited to only black backgrounds.
In the photograph of the red-eyed tree frog, I used a 15mm macro lens with a single off-camera flash that had a 26 inch softbox attached to it. By adjusting the exposure in camera for the background I wanted, which was dark and moody but with some details of the rainforest, I then the flash exposure to illuminate the frog and ultimately balance the two exposures based on the type of photograph I wanted to make.
Balancing the ambient light with the flash exposure is a powerful technique when working with wide angle closeup photography because it allows us to bring in some of the environment around our subject. And it’s this environment that helps an image tell a story.
Can you spot an obvious HDR (high dynamic range) photograph? You know, where the photographer blended 3 or more photographs together? Yes, we can create HDR images that are not so obvious, but the reason that some are is because of the lack of shadow. When we remove shadows from our photographs, we create something that looks unnatural. HDR is a prime example. And so is overly flashed photographs when the photographer kept the flash on camera. We all remember those awful disposable Kodak cameras and what they did to photographs when the flash came on. Don’t be that photographer.
This is why my telescoping flash extender is without a doubt my most beloved flash accessory. In conjunction with the RRS flash bracket, and I can move this thing down to the side and place my flash anywhere up to 90-degrees to my macro subject. The more side light a subject, the more shadow that is created.
All of this is subjective of course. Just because I like dramatic lighting with dark moody backgrounds and lots of shadows does not mean that you will. What you think is a good lighting ratio between the ambient light and subject will be entirely a matter taste on your own part. Maybe you like a perfectly balanced lighting ratio. Maybe you like a black background because of how it brings 100% of the attention to the beauty of the subject itself. Neither is right, and neither is wrong. You have to develop your own personal style built upon what appeals to you. When it comes to the technical side of things, there is a right and wrong way to go about this thing we call photography. But when it comes to how the photograph LOOKS, the mood, the emotion, the composition, the feeling it creates in you the artist: DO WHAT APPEALS TO YOU AND ONLY YOU. There is nothing more maddening as an educator and an artist than to watch other professional photographers tell their audience that their way is the right way, the only way. It’s not.
With a few balanced compositions under my belt, those standard sort of portraits and journalistic shots if you will, I begin cranking down my camera’s exposure. The lower I get it, the darker the background becomes and the more prominent my flash is as the only source of light. But with this lowering of the camera’s exposure, I also work to bring my flash further away from my camera and closer to my subject.
The further my flash gets off axis with me, the more dramatic the light will be because of those shadows. Additionally, the closer the light is to my subject the more dramatic it will be as well. I am using a Micro Apollo Softbox on the end of my flash which helps to both diffuse and spread the light. But the closer to the subject, the more concentrated the light will be. The further away from the subject, the more spread and the softer it will be. The exact distance you hold your flash from the subject matters greatly. Do you like a softer edge to your shadows? Pull it back. Do you like a sharper distinction between light and shadows with a touch more contrast to boot? Move it closer.
With the more typical portraits I started with here, I kept the flash about 2 feet away from my subject. This created less of a defined edge between light and dark. It helped to fill in the shadows I did create just a bit and gave the entire image a softer feel to it.
But with the darker images here, I moved in close. How close? Inches from my subject. In fact, in all of these darker and moodier photographs, the flash was positioned just barely outside of the frame. And again, this is where TTL mode comes into play when working in the field like this. I have the freedom to experiment with the distance of my flash to the subject without having to do math every time I move a little.
As the light began to fade and the drone of cicadas was replaced by the incessant whine of infinite numbers of mosquitoes, it was time to hike back to the vehicle. Frogs were finally beginning to pull themselves up to the edge of the pitcher plants as they readied to join in with the evening symphony of amphibians here. I wanted to stop. I wanted to photograph every single one. My little treefrog had been, well, a very little treefrog in a very large pitcher plant. Much like photographing birds, perch size matters. But alas, dinner plans with friends in town lured me on, pausing only to grab a few photographs of a stand of pitcher plants whose genetic makeup offered up a slight mutation filling its leaves with crimson red instead of the typical yellowish green.
The biological diversity of this place is overwhelming. So unsuspecting. Yet so much life. And this is what I love about flash and macro photography in general. It gives us the tools needed to truly celebrate the beauty of life in all of its many forms. Every photographer wants elk and bears. They are big. They’re charismatic. But so much goes unnoticed right in our own backyards that if we slowed down enough to just pay attention, we could fill every day of our lives creating art.
In this article, I only lay out the key points you need to understand for getting started with a single flash used for primary light in macro photography. There are so many other ways of using flash in then the field such as two flash unit setups for macro, fill flash for birds, and multi-flash hummingbird setups to name just a few. I will be covering all of these in future issues of the Journal.
Putting it all together. . .
When using flash, you are working with two separate exposures at the exact same time: your camera’s exposure and your flash’s exposure. Set them separately.
Set your camera’s exposure for the background (ambient light). Reduce exposure for darker background. Increase exposure for brighter backgrounds.
Set your flash exposure for the subject itself.
Use manual mode if you are in a controlled environment where distance between your flash and subject will not change.
Use TTL mode in all other situations and adjust the flash exposure using Flash Exposure Compensation (FEC) so you do not need to do the math associated with the inverse square law.
Put your camera into High Speed Sync mode so you have total control over the camera’s exposure and your depth of field. Otherwise, you will be limited to 1/250th of a second or slower.
When your flash is coming from the same direction as your camera, less flash is more. Use very sparingly as fill flash.
If you can get your flash of axis with your camera, you can then use it as a primary source of light.
The closer your flash is to your subject, the less contrast you will create and the softer the transition from highlights to shadows, e.g. the more natural looking the image will be.
The closer your flash gets to 90-degrees from your subject, the more shadows you will create.
Shadows are an important part of photography. They define edges. They give depth, dimension, and create detail. You always want to create or maintain shadows to give the photograph a natural look.
My primary macro flash accessories are as follows:
RRS flash bracket
RRS telescoping flash extender
RRS MPR-CL II rail with integral clamp (7.4”). This connects to camera plate so I can use a flash bracket on lenses that don’t have a tripod color.
Micro Apollo Soft Box