A jewel of a beetle

I really wish I had a photomicrography setup like the one that Sam Heads has at the University of Illinois for imaging preserved specimens. Alas, insect taxonomy is “just a hobby” for me, and any specimen photography I wish to do must be done with my field camera equipment. Of course, poverty prompts creativity (not that I consider a Canon 50D with an MP-E 65mm macro lens and MT-24EX twin flash unit a sign of poverty), and after a bit of tinkering and fiddling I’ve figured out a way to setup the specimen and flash units to create images of pinned specimens that I think are more than adequate for publication in taxonomic papers.

Here is one I did recently of the jewel beetle Actenodes calcaratus (family Buprestidae). This species is broadly distributed from the southwestern U.S. through Mexico and into Central America, where it breeds in dead branches of a variety of mostly fabaceous trees such as Acacia and Prosopis. During several trips to southern Mexico in recent years, Chuck Bellamy and I collected two new species of Actenodes that look very similar to A. calcaratus but differ in several important characters, primarily surface sculpture, the form and male coloration of the face, and male genitalia. A manuscript describing these two species and containing this and similar images of the new species was recently submitted for publication. Though not quite as razor-sharp as images created through focus-stacking processes, it still shows good detail and even lighting. What do you think?¹

¹ For those who find the pin head distracting, I am not a proponent of cloning out pin heads, debris, or other imperfections on images of preserved specimens in taxonomic papers. Other enhancements such as levels, sharpness, contrast, etc. are fine since these are all influenced greatly by lighting, but otherwise I believe the specimen needs to be presented exactly as it appears. A possible alternative is to remove the pin for imaging, but this presents a risk of damage to the specimen that is of questionable benefit in the case of non-type specimens—and downright irresponsible for primary types. Another alternative is to thoroughly clean and image the specimen prior to mounting, but this is rarely feasible as in most cases it is only after the specimen is mounted and studied further that its status as a new species is realized.

Actenodes calcaratus | MEXICO: Guerrero, Hwy 95, 5 km S Milpillas, 7.vii.1992, "big dead tree", G. H. Nelson [FSCA]. Male plesiotype.

Actenodes calcaratus | MEXICO: Guerrero, Hwy 95, 5 km S Milpillas, 7.vii.1992, “big dead tree”, G. H. Nelson [FSCA]. Male plesiotype.

Copyright © Ted C. MacRae 2013

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About Ted C. MacRae

Ted C. MacRae is a research entomologist by vocation and beetle taxonomist by avocation. Areas of expertise in the latter include worldwide jewel beetles (Buprestidae) and North American longhorned beetles (Cerambycidae). More recent work has focused on North American tiger beetles (Cicindelidae) and their distribution, ecology, and conservation.
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13 Responses to A jewel of a beetle

  1. Tim Eisele says:

    “(not that I consider a Canon 50D with an MP-E 65mm macro lens and MT-24EX twin flash unit a sign of poverty)”

    Well, maybe *after* you buy them, they are . . .

    I’m actually not so sure that your optics are much inferior to what Sam Heads has. You just need the microscope stage, a mount for your camera, and the imaging software.

    • Sam Heads says:

      Indeed, the MP-E 65 are as good as (if not superior to) the optics on the Olympus scope used in our imaging system. You can actually achieve very similar results using a good tripod and the stacking functions in Photoshop CS5 (see my other comment below).

    • Agreed – it’s not the optics that are limiting, but the ability to stabilize and adequately illuminate the specimen. While I would prefer having a better system, there is a bit of pride that comes from being able to produce a good image with just a hand-held setup.

  2. Sam Heads says:

    Great image Ted. I too occasionally use my Canon DSLR and macro lenses for imaging of pinned material and have successfully managed to use the focus stacking feature in Photoshop CS5 to achieve good results. For example, this image (http://flic.kr/p/btbXFM) was generated using a Rebel T3, MP-E 65 and MT24-EX for use in this paper (http://goo.gl/iGg98). It’s a stack of 5 images. The key was a good tripod, and I use a Velbon VS-443 D (http://www.velbon.biz/product/VS/index.html). The geared slide is super useful for incrementally moving the camera closer to, or further away from, the specimen to capture a series of images for later stacking in Photoshop.

    • That tripod is actually quite reasonably priced. I presume, based on the quality of the photo you link to, that controlling the amount of movement with the geared slide is not an issue? If not, this seems like a quite reasonable compromise over having to buy both a tripod and a focusing rail. (Yes, believe it or not I do not even own a tripod!)

      • Sam Heads says:

        I’ve had no problem so far controlling movement using the geared slide. I also find the 360 degree boom very useful as you can effectively turn the tripod into a copy stand. I’m sure that focusing rails allow much finer adjustment, but they also cost significantly more. In addition to the tripod, I also use a remote shutter release so I don’t have to touch the camera at all once I’ve got it in the right place.

        Incidentally, you are always welcome to use the photomicrography system we have here in the lab. We’re not all that far away after all.

        • That tripod just might be the thing to get me to try some focus stacking – possibly even in the field. The cost of focusing rails on top of a tripod has always put me off, since I don’t really do that much specimen imaging, which has put me off thinking I even need a tripod, etc. etc.

          Use of your system or no, I’d like to get up there anyway to see your lab and spend some time with you. I’ll contact you with some ideas.

  3. Looks good! The blue and red bands are a nice decorative touch.. It looks beaded, but are those actually hairs?

    What Tim said, but a simple horizontal set-up with macro rail and free Combine Z would do the focus-stacking job for a relatively large specimen like this.

    • The “beads/hairs” are actually small punctures, each with a tiny backward-directed hair arising from it.

      Tripod, focusing rail, wide-angle lens, flash bracket/articulating arms – I just don’t know what to do with all this money that isn’t burning a hole in my pocket! :) At least the CombineZ software is free.

  4. You are your own worst critic, Ted. the image is gorgeous!

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