This post may seem like déjà vu to some of you, as it is my third featuring our common woodland tiger beetle species, Cicindela sexguttata (six-spotted tiger beetle). However, this post is as much a photography lesson as it is insect post, and when I say photography lesson I mean for myself – I’m not yet anywhere near the point where I feel qualified to dole out photography advice to others.

The last weekend of May, I returned to nearby Shaw Nature Reserve in hopes of photographing Cicindela unipunctata (one-spotted tiger beetle). This large, nearly flightless species has been recorded broadly across the eastern U.S. but is not encountered all that commonly. It is among the few species that seem to prefer more shaded woodland habitats (Pearson et al. 2006); however, its ecology is still not well understood. I had hoped to find it during my first outing with the new camera setup, but it was not to be and I had to settle for C. sexguttata as the first tiger beetle subject for my camera’s maiden voyage.   On this return visit, I arrived at the preserve shortly before noon and proceeded to walk back and forth along the trails where my colleague, Chris Brown, had noted healthy populations last year and one individual just three weeks ago.  For four hours, I gazed intently at the path in front of me in hopes of seeing the beetle – usually blending well with the ground because of its dull brown upper surface and noticed only because of its clumsy manner of running when disturbed.  All to no avail.  Of course, our old friend C. sexguttata was still present in good numbers, and since I wasn’t completely happy with the results of my first photo shoot of this species with the new camera I decided to try it again.

My main criticism of the initial photographs of this species was the harshness of the lighting.  I suspected that diffusers of some type would give a better result, so for this outing I covered the flash heads with small plastic diffuser caps that I had purchased with the flash unit.  The following series of photographs compare the results with and without the diffuser caps.  The photos have been left unenhanced but are reduced from their original size to 1200×800 pixels.  All of the photographs were taken using a Canon EF 100mm macro lens on a Canon EOS 50D, ISO 100, exposure 1/250 sec, and MT-24EX twin flash unit.  Click on the photos to see the enlarged version after reading the discussion of each.

This first photo is from the first session, during which I ran the flash unit at 1/4 power without diffuser caps.  The conditions were rather bright, and it required a relatively high f-stop (f/20) to get the exposure right.  This resulted in very good depth of field, but as you can see the lighting is rather harsh with bright highlights due to the brilliant, metallic coloration of the beetle.

In this photograph, I reduced the flash power to 1/8 and used the diffuser caps.  This softened the light considerably and removed much of the harsh highlighting.  However, I had to open up the aperature to f/10 in order to get good exposure, and as a result the depth of field really suffered.  Apparently the diffuser caps also reduce the amount of light from the flash, which combined with reducing the power to 1/8 substantially lowered the light levels.

I then increased the flash back up to 1/4 power but kept the diffuser caps in place.  This allowed me to increase the f-stop to f/13, which resulted in much better depth of field.  Since this photograph was taken in fairly bright conditions, this suggests that I might want to go up to 1/2 power flash in lower light situations if I want to maintain a higher f-stop.  I am very happy with this photograph – the lighting is even with no harshness, and virtually the entire beetle from foreground to background is in focus.  A little post-processing might still be helpful for reducing the shadows a bit, but otherwise I think this is a pretty good standard to shoot for with my future tiger beetle photographs.

As the saying goes, patience rewards those who wait, and a short time before I needed to leave, I finally saw the first C. unipunctata.  I was lucky enough to see it on the path without first disturbing it and was able to slowly crouch down into position and roll off a series of photos from this angle.  The photo I share here seemed to be the best of the series, but as I tried to shift to get a different view the little bugger began to bolt.  I blocked his escape with my hands until he seemed to settle down and then looked for him in the viewfinder, but I couldn’t find him – he had bolted as soon as I took my eye off of him, never to be seen again.  It amazes me how a relatively large beetle such as this – flightless even – can disappear completely amongst the vegetation.  Nevertheless, I accomplished my goal of getting at least one good photograph of this species, and you can be sure that I’ll be back to try for more.

I know there are several quite capable insect macrophotographers out there that occasionally read this blog – I encourage any comments or feedback that you might have on the techniques I have discussed here.

Copyright © Ted C. MacRae 2009

REFERENCE:

Pearson, D. L., C. B. Knisley and C. J. Kazilek. 2006. A Field Guide to the Tiger Beetles of the United States and Canada. Oxford University Press, New York, 227 pp.

Chris Wirth just wrote a nice post summarizing the use of digital SLR camera systems for insect macrophotography.  Having just gone through the process of upgrading to a dSLR system from a point-and-shoot myself, I can relate to much of what he discusses.  The advantages are clear – higher image quality, far greater magnification capabilities, and control over lighting, shutter speed, aperture, etc.  He also discusses the disadvantages – chiefly co$t, weight, and initial learning curve.  He ends with this recommendation:

…if you are serious about insect photography and have the monetary resources, a DSLR is your only choice. Again, as of yet, nothing else provides similar quality or control.

Although I dabbled in insect photography many years ago with an Olympus OM-10 SLR film camera and a Zeiko 50mm macro lens, it wasn’t until I started this blog 18 months ago that I started making a real effort to photograph insects, using a Panasonic Lumix DMC-FX3 point-and-shoot that my dad had given to me for my birthday earlier that year. At first, I was amazed at the macro capabilities of this little camera – point, autofocus, and shoot! Yes, the photo needed to be cropped, and the reliance on natural light was not only limiting but often resulted in deep shadows – but nothing a little Photoshop couldn’t fix! It wasn’t long, however, before I began to see the limitations – not just on size, with tiger beetles being near the lower end of the size of subject I could photograph, but also with the quality of the images themselves. The perfectionist in me started envisioning what I could do if only I had the equipment. Mind you, I’m proud of the photographs I’ve acquired over the past months, given what I had to work with. But now that I have the equipment to do it right, I see a conflict on the horizon – do I attempt to go back and re-photograph all of those species that I’ve already photographed, or do I move on and and not look back? Perhaps a little of both is the best approach.

In the meantime, I’ve got to learn how to use this camera. The first weekend I had it, I accompanied my friend and colleague, Chris Brown, to nearby Shaw Nature Reserve, where Chris had previously noted good populations of the very uncommon Cicindela unipunctata (one-spotted tiger beetle) [now Cylindera unipunctata, fide Erwin & Pearson 2008 – more on this in a future post] – what a fantastic species for my first photo shoot with the new setup. Unfortunately, we did not find this species (although I will eventually). Instead, I focused on the very prolific population of Cicindela sexguttata (six-spotted tiger beetle) that we found at this site. Cicindela sexguttata is the one tiger beetle that is, more than any other North American species, known by entomologists and non-entomologists alike. Anyone who has ever taken a walk in the eastern forests during spring has encountered this beetle – flashing brilliant green in the dappled sunlight, always a few yards ahead on the path. While belonging to the “spring/fall” group of species, adults of this species break ranks and stay put in their burrows during fall while other spring/fall species come out and explore for a bit before digging back in for the winter (Pearson et al. 2006). While many individuals do show the six white spots on the elytra that give the species its common name, this character is actually quite variable, with some northern populations completely lacking spots.

As tiger beetles go, it’s one of the more difficult to photograph because of its shiny, metallic coloration (as opposed to the flat, dull coloration of Cyl. unipunctata). This was probably a good thing in terms of starting the learning process. I limited myself during this session to the 100mm macro lens (leaving the 1-5x beast for another day), with the photographs shown here being some of the better ones. While I like them, I also see a few things I did wrong. First was the flash – I set the flash units to 1/4 power and didn’t use any kind of diffusers, and as a result the lighting turned out harsh – especially for this brilliantly-colored, metallic species. I’ve softened the highlights a little bit in Photoshop, but the results are still not as good as if I had used a lower power and diffused the light, and ultimately my goal is to achieve well lit photographs that do not need post-processing to make them look right. Other than that, the day was mostly about getting used to handling the camera and learning how to judge f-stop based on my manual settings for exposure (1/200 sec) and ISO (100). The single individuals (above) were taken in full sunlight, and in that situation my f-stops tended to be too low (resulting in overexposure), while the mating pair was in shade where my f-stops tended too high (underexposed). Next time, I’ll try the diffusers I bought, use less flash power, and do more f-stop bracketing until I get a good feel for what I need in a given situation.

For comparison, here is the one C. sexguttata photograph I took with the point-and-shoot last year. This is about as good a photograph as I could get of this species using that camera. Besides being heavily cropped, it differs by being not very well exposed (despite post brightening), showing heavy shadows (despite post lightening), and lacking detail.

REFERENCES:

Erwin, T. L. and D. L. Pearson. 2008. A treatise on the Western Hemisphere Caraboidea (Coleoptera). Their classification, distributions, and ways of life. Volume II (Carabidae-Nebriiformes 2-Cicindelitae). Pensoft Series Faunistica 84. Pensoft Publishers, Sofia, 400 pp. + 33 color plates.

Pearson, D. L., C. B. Knisley and C. J. Kazilek. 2006. A Field Guide to the Tiger Beetles of the United States and Canada. Oxford University Press, New York, 227 pp.

Copyright © Ted C. MacRae 2009