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.

Flash 1/4 power without diffuser caps, f/20

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.

Flash 1/8 power flash with diffuser caps, f/10

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.

Flash 1/4 power with diffuser caps, f/13

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.

Cicindela unipunctata - flash 1/8 power with diffuser caps, f/13

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.