The Art of Composition part 5
Should I stick a teleconverter on my lens or just crop in Lightroom? This is a question we all face in the field at some time or another. Both are potential solutions for “getting closer.” Both come with their drawbacks.
While I spend more time talking and writing about how to find and physically get closer to animals than any other wildlife photographer out there right now, there are times when we just simply can’t make it happen the way we want to. Whether it’s a sensitive situation, the species is far too weary, or far too dangerous, sometimes we can’t zoom with our feet; sometimes we just need more reach than our lens allows.
Be it a teleconverter or cropping in post, both solutions have an impact on the depth of field of an image. One good, another bad. And for this reason, I think it’s important to touch on this topic so you can get an idea of how these choices ultimately affect your photography.
Today, photographers are obsessed with their megapixels. Nikon and Sony’s flagship cameras are around 50mp. For a decade or more, this has been one of the driving forces behind what consumers wanted and how camera manufacturers responded. The idea being that bigger is always going to be better.
For those photographers who do things with their images other than just post to Facebook and Instagram, megapixels matter little unless you want to print really big. Personally, I have two Nikon Z9 cameras that I shoot almost exclusively with these days and when it comes to a fine art print larger than three feet in size, I appreciate the 45mp sensor I’m working with.
But most wildlife photographers aren’t considering how more megapixels makes printing large a little easier. Instead, the obsession with megapixels tends to come down to one single thing: cropping.
We have all done it. Each and every one of us has made photographs with the intention of cropping it in Photoshop or Lightroom. Maybe we couldn’t get close enough. Maybe there was a river in between us and our subject. Maybe we didn’t want to be charged by a rampaging bull elk in the rut. Or maybe we were just being lazy. Whatever the reason, in the end, we did ourselves a disservice.
Why?
Because depth of field is a function of distance, distance to your subject and distance of your subject to the background.
Let’s say we are photographing a large bird at a distance of one hundred yards away flying in front of a forest using something like a Nikon 180-600 or Sony 200-600mm lens. For the sake of argument, and to momentarily excuse you for photographing a bird from such distances, let’s say you are sitting on the bow of a boat working at a seabird nesting colony and the species in question is a red-billed tropicbird - meaning, these are the photos I have access to at the moment to show as examples =).
Both lenses have maximum apertures of f/6.3 at this focal length (f/7.1 if you’re using the Canon 100-500). An aperture of f/6.3 isn’t a bad thing when it comes to photographing birds in flight. Often, we want to work with a little more depth of field in order to create something of a safety net for our focus given the erratic behavior of birds in flight. So, a smaller aperture in the f/5.6 – f/8 range is pretty typical for most bird in flight photography.
At this distance (100 meters), with this focal length (600mm), using this aperture (f/6.3), your depth of field will be just shy of 30 feet.
Picture the bubble around your bird. Everything inside of that bubble appears to be in focus. As things move further and further away from the bubble, the more out-of-focus things appear.
Now, that forest in the background isn’t neutral. No background is neutral. They either help or they hurt for various reasons.
Forests are filled with trees and branches and leaves. In the tropics, where red-billed tropicbirds are found, often those trees are broad leafed or palms. And from the trunks to the branches to the palm fronds waving in the Caribbean breeze, from the perspective of composition, trees and forests are made up of countless lines. Lines demand attention. Lines grab our eyes. Lines lead our eyes. Like backgrounds, lines are not neutral. Lines either help or hurt our photographs. We must be careful when we have distinct and noticeable lines in our compositions because unless they are properly arranged, they will distract and destroy a composition in a heartbeat.
This is where understanding the nuances of depth of field comes into play. By understanding how to control depth of field, by understanding how our choices impact our depth of field, we can mitigate those distracting backgrounds filled with sticks and twigs and tree trunks and palm fronds. But not if we depend on cropping our photos.
A thirty-foot depth of field bubble around our subject is pretty big. If the bird is anywhere near the trees, so much detail will shine through in the background that you will have a devil of a time trying to create separation between those distracting details and your subject. There is nothing inherently wrong with showing the details of the forest. It’s often these details that are used to help tell stories for photojournalists, for instance. But there is a difference between storytelling and distraction, and depth of field plays a big role in all that.
As if adding all that extra detail into the background wasn’t bad enough, now we take that photograph and crop in to make the subject appear larger. But it’s not just the bird that gets bigger. We also make those background details bigger, the lines more pronounced, the distractions a larger and more noticeable part of the composition as well.
A Tale of Two Photos. In these two examples, I was working in the same location, with the same background, with the same species of birds flying roughly the same distance away from the background. The only difference here is how close I was to the birds myself - meaning, how much closer we brought the boat in to the island. Both of these photographs are sellable. After spending two days riding out swells on the Caribbean photographing at this seabird colony, I decided to begin working with different types of compositions that included the palm filled backgrounds available on a certain portion of this big rock sticking up out of the sea. As you can see from the top image, I was further away than I was when I made the bottom image. It took a lot of trashed photos before I was able to create the top one due to all of those strong lines in the background. With the bottom image, however, you can see that the palm fronds are much more out-of-focus, making it easier to work with. While I prefer to top photograph personally, because of how I managed to capture the bird with an artful arrangement of the palm fronds, you can see how easily this whole situation is destroyed because of that same detail. If you are someone who finds that their backgrounds are often cluttered or distracting, stop cropping your images and start figuring out how to get closer to the subject or begin using teleconverters. If you want to learn more about backgrounds in bird in flight photography, don't miss the upcoming issue of PhotoWILD Magazine.
Of course, some folks have mobility issues. Some cannot afford longer lenses. Some cannot carry longer lenses. I completely understand this. And hey, we all do this thing called wildlife photography for our own personal reasons. Maybe it’s a matter of getting out of the house, enjoying nature, the thrill of the hunt, or maybe it’s art, maybe it’s to make money, or maybe it’s to “win friends and influence people”. But when it comes to the visual art of all this, the look and feel, how we make our subjects stand out, and how we arrange the picture space, approaching the subject as though you can crop in later truly makes a big difference in the end photograph. For me, as a working artist, depending upon megapixels for the ability to crop later is a recipe for disaster.
All too often, I see photographers choosing to do this simply because they can. I’m sure you have heard plenty of folks talk about this – especially in the field. “Oh, I can just crop in later. . .” But, just like working with an APS-C sensor, cropping in on your image doesn’t suddenly change the lens and all the physics involved with light and magnification.
This is why a discussion about DOF is so important when it comes to composition to begin with. This is why I am spending so much time talking about these things. Sometimes, we NEED to isolate our subject from its environment as much as possible, and the only way to do this is by working with the shallowest depths of field.
I admit, though, that you cannot always get closer. Some subjects are far too dangerous. Some situations are not conducive. Sometimes, there are laws in place dictating this. Sometimes, in the case of our nesting seabird colony and flying red-billed tropicbirds, the seas may be too rough and the reflective waves too dangerous to get closer. So, what’s an alternative to cropping?
Enter: the teleconverter.
You are probably already familiar with teleconverters, so I don’t need to go into a description of what these are and how they work. However, I will say that I never work with anything larger than a 1.4x teleconverter myself. Hard stop. NEVER.
Anytime we use a teleconverter (TC), we lose at least one full f/stop from our lens. So, if we are using a 1.4x TC on a 600mm f/6.3 lens, this means the camera will automatically stop down to to f/9. This isn’t a choice, of course. You don’t decide to do this or not. Your camera and lens will do this automatically for you. It simply won’t allow you to work at f/6.3.
At f/9, you have effectively cut the light in half from what it would be at f/6.3. This means one full stop of light is lost. And that, in turn, means INCREASED DOF.
So, on the surface, it all seems counterintuitive. If I want less DOF, how on earth is working with a smaller aperture going to help me?!?
It’s a logical question.
However, the other major thing that affects DOF, as I have already written about in this series, is focal length.
A 600mm f/6.3 lens with a 1.4x TC attached becomes a 840mm f/9 lens. And this increase in focal length more than cancels out the DOF loss from the stop down to f/9.
Calculators again…
Using the example again of a red-billed tropicbird at 100 yards (300 feet), only this time with 840mm at f/9, we achieve a DOF of about 20 feet.
Twenty feet isn’t exactly a shallow depth of field here, but using a teleconverter, as opposed to cropping, increases the size of your subject in the composition (while retaining your resolution) and does shave about 10 feet off the depth of field. And when it comes to controlling the picture space, 10 feet can make a huge difference.
Frankly, there is not true substitute for getting closer to a subject or working with a longer lens when it comes to depth of field and bokeh. But when I simply cannot get closer, when it’s absolutely out of the question, teleconverters are the best option for me. It does mean that I will still need to think long and hard about my composition and compose creatively, but it also means that I am working with the shallowest DOF possible for the situation.
Now, I primarily shoot Nikon equipment and in my humble opinion, until very recently Nikon couldn’t make a decent teleconverter to save their life. Canon and Sony? No problem. Rock solid. But Nikon? Using a teleconverter was quite often a big pill to swallow because of the degradation of image quality and sharpness. Of all the lens / TC combos I used in the days of DSLR cameras, it was the Nikon 200-400 VRII f/4 lens with the 1.4TC III that was the best. However, to get results I was truly happy with, I would have to typically stop down to f/8.
This was one of the big downsides to using a teleconverter for a long time, regardless of camera manufacturer. All of this changed with mirrorless technology, however. By removing the mirrors from the cameras themselves and focusing directly off the sensor, camera manufacturers across the board were able to make teleconverters that were much sharper and much more reliable. And as a result, I now have complete confidence in teleconverters even as a Nikon shooter.
But that’s enough about that.
If your someone who likes to depend upon your high-resolution sensor to crop in afterword, I recommend looking into using a 1.4x TC with your lens instead. Better yet, just get closer with your feet if at all possible.
Although using teleconverters does equate to a smaller working aperture, the increase in focal length will have a noticeable effect on your DOF and compensate for the change in f/stop. This in turn makes composing a little less challenging — especially when you are dealing with a cluttered environment.