I’ll confess right off that I really love this image as I think I succeeded in making something nice and dramatic out of an animal that is not especially pretty and doesn’t really do much, the green iguana (Iguana iguana). In Costa Rica, there’s a pretty well-known restaurant where wild green iguanas hang out in the trees over a meandering river, and I stop there with many of my workshop groups as it’s a great place to get eye level with these interesting creatures. Plus the place has great ice cream cones!
Green iguanas (Iguana iguana) often hang out together, dozing and eating leaves (they’re vegetarians). I liked the way these guys were stacked up, and when I saw one iguana begin to become active, I quickly shot at a wide open aperture with a telephoto lens for shallow depth of field as the “iguana king” surveyed his little domain 🙂
Here’s the thought process I went through while taking this photo.
First, in terms of gear, my 300 mm with a max. aperture of f2.8 was a great choice for me here because it allows for the shallow depth of field look that I love and it gives me a fast shutter speed when handholding. In this case, one sometimes stands on a bridge over the river while pineapple-laden trucks roll past. Your tripod might well end up as a bipod or monopod if you’re not careful!
Second, I needed to consider which camera to use. At the time of this picture, I had a full-frame Canon 5D and 1.6x sensor 40D. The latter body would give me more effective magnification at a given working distance but a small sensor body offers two disadvantages in this situation. First, larger sensors offer less depth-of-field (see here for a fantastic, thorough explanation of this phenomenon). Plus the image quality of the full-frame body is always nicer than that of a 1.6x sensor body in my opinion. The 40D did have better autofocus but in this situation, fast autofocus wasn’t an issue. So, 5D it was.
Third, I had my flash mounted. Did I want to use it? When I came upon this scene, I knew I’d want to shoot through some foreground iguanas. When shooting through a foreground object, flash tends to light it up, and that’s not what I wanted here. Fortunately, I had nice bright overcast light to work with, which was perfect.
Fourth, what about my settings? I knew I wanted to use f2.8 to get the shallowest possible depth of field for that dreamy deep forest look. Plus a fast aperture would help to get me a decent shutter speed. I decided that 1/200 was good enough as my lens has pretty good image stabilization, and I was able to rest my elbows on the bridge’s guardrail. That put me at ISO 320, which was just fine. I could have gone up more in ISO but even with the good high ISO performance of the full-frame 5D, I decided that it was better to keep the decent shutter speed I have and be able to produce an image with lower noise. The shutter speed/ISO noise tradeoff is always an important issue to consider.
Fifth, the composition here was key. There were a lot of iguanas! I walked around a bit until I saw this iguana lifting his head a bit while the others napped. I composed carefully to have the out of focus iguanas all contribute to making the main iguana really pop out, and I made sure to have the main iguana’s eye right by one of the thirds of the frame (the power points — see below). Composing according to the rule of thirds is not an ironclad rule, but I thought it would work well for this situation.
Sixth, to meter the scene, I decided to work in aperture priority and evaluative metering mode. Most of the tones in the scene were darker than the face of the main iguana. So, I knew that I would have to apply a bit of negative exposure compensation, in this case, -1/3 stop did the trick.
Seventh, from there I simply selected the autofocus point closest to the iguana’s eye and used that to autofocus. I have my autofocus on one of the back buttons of my camera, totally decoupled from the shutter button. Thus I was able to lock focus and recompose before snapping the shutter.
I hope you’ve enjoyed this post and the thought process behind the image. Successful nature photography is all about previsualizing an image (even when shooting action or capturing a fleeting moment), analyzing the tradeoffs that your previsualized image entails, and then making choices. Hopefully this little article will give you some ideas for the next time that you’re out in the field photographing.