The days of yore, part one

Okay, I admit it: I have no idea what the hell “yore” is. But since it’s not the season for nature photography, I’m hearkening (yeah, ditto) back to a time when it was. That I’m intending to make this an occasional habit is indicated by the ‘part one’ in the title…

This past summer, a tree alongside the house played host to a fairly common sight, which was a minor invasion of planthoppers. Gardeners usually consider these a pest, because of the damage they can do to preferred plants given adequate numbers of them, but I’m more egalitarian – it’s all grist for the mill (I’m just slamming out these ancient phrases, aren’t I?) Especially since they have an interesting relationship with another insect.

In nymph form, like the brown example at right, they display a curious ‘tail,’ which is actually their fecal matter, unused material filtered from the sap that serves as their food. While the species shown here (almost certainly Acanalonia conica, though at least one source indicates that the nymph form is green instead) displays only a simple plume reminiscent of cotton candy, some planthopper species produce long and distinctive ‘tails,’ in some cases appearing iridescent from the light diffracted through their crystalline structure. Once they become adults like the green examples here, however, things change a little bit.

In both forms, they attach themselves to plant stems with a proboscis and suck sap from the plant, largely remaining in place for longer periods of time. The adults excrete waste in liquid form, generally a drop every five to ten minutes. What the planthoppers have no use for, some ant species do, and it’s usually a matter of time before an ant colony discovers a planthopper colony and the milking begins. As the planthopper squeezes out a deuce, it usually remains attached to their hind end for a minute or two, and if the ants are on schedule, they will come by and suck up the offering, using this as their own food.

I first witnessed this one evening as I was examining the trees by flashlight, while the camera was not in hand. This, naturally enough, was a challenge, so I returned the next day and set up a rig to capture this behavior as it occurred. This is easier said than done, since my planthopper subject here is about 8 mm long, so I was working in fairly high magnification. And that means that depth-of-field is quite short, so the range of sharp focus is tiny. The slightest breeze would move the supporting branch, carrying my subject well out of focus, but even when perfectly steady, the planthopper could be in focus but the ant, approaching ever so slightly from the side, would not be. Moreover, the planthoppers usually chose spots under a leaf to retain some shade, and I can’t say that I blamed them, because I was sweating buckets getting these daytime pics. But that shade also meant reducing light and contrast. Coupling this with the small aperture being used to get the highest depth-of-field, the light was reduced so much that the longer shutter speeds to compensate meant that the hyperactive ants, which never held still even while drinking, would be blurred out. So this also required strobe units to provide enough light for a fast shutter, offset to the side for better light characteristics. This occasionally leads to its own problems.

Okay, quick explanation here. Small aperture means more depth-of-field, but less light – this results in underexposure unless you lengthen the time the shutter is open (usually producing motion blur) or add some light from a strobe. Now, the light from a strobe drops off exponentially, in inverse-square proportions, meaning at twice a given distance, your photo subject receives only 1/4 the amount of light; at four times the distance, only 1/16th. When working with close subjects only a dozen centimeters or so from the camera, it’s very easy for the light to drop off to almost nothing on the background leaves, even when they’re little more than a hand’s length further away. This light falloff, and the small apertures, are what produces the dark backgrounds in so many insect photos even when taken in daylight. To compensate, you can add another strobe unit specifically for the background, or use light diffusers that allow the background to receive more light while your subject receives it only peripherally, balancing out the affect.

None of this is very portable, and usually requires not only a tripod, but an extra bracket for the main strobe, and perhaps a stand for the secondary – not something that’s going to work well with moving subjects. That’s why I could even accomplish this with the planthoppers, who obligingly stayed put even when I loomed close, counting on their camouflage for protection. Ants don’t seem to worry about anything and constantly ran back and forth no matter what my actions, but they presented their own challenge anyway. Shiny black bodies are difficult to photograph, since it takes a certain light angle to capture detail properly; otherwise you get very little to distinguish, as seen above. A good softbox diffuses the light and makes ant bodies stand out better, but even small examples of these are bulky and don’t lend themselves to use within the branches of a tree.

So sometimes I cheat a bit, and set up my own conditions. Here, a nymph was collected on a leaf and carried over to a table on the porch, where the leaf was placed in a clamp (actually a “third hand” soldering rig, a huge help for macro shooters) and the lighting adjusted as needed. Even when the nymph wanted to move around, all I had to do was slide the rig along the table to keep it centered, and rotate as needed to get the facial angle I wanted. This allows for nice detail shots, helpful for both identification and biological uses, while still remaining a fairly natural setting. That’s one of the benefits to shooting macro: an appropriate “set” can be a few centimeters across and doesn’t require a team of gaffers.

If you were paying attention, you have noticed the difference in eye color seen in these images. This is not indicative of different species (though the pale green one two pics up certainly is,) but instead different times of day. For reasons I have yet to determine, planthoppers (and other insect species) have eyes that change color when it gets dark, which means the red-eyed examples show that I was actually shooting at night. This can be more useful than you might have thought, partially because of the difference in appearance or behavior of your subjects, but also because the breeze has often died down and the plants are holding still better. Not to mention that there’s no longer any chance of sunburn or sunstroke, which I figured we could all use the reminder of right now when the weather’s cold.

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