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Posts Tagged ‘compound eyes’

Dragonflies have amazing compound eyes that wrap around their heads. With up to 30,000 facets (ommatidia, to be technical), dragonflies have incredible vision and can even see colors beyond human visual capabilities, like UV light. For an easy to read discussion about dragonfly eyes, i.e. not overly scientific, check out this posting by “grrl Scientist” that was posted on scienceblogs.com.

I captured this close-up image of a Great Blue Skimmer dragonfly (Libellula vibrans) yesterday at Occoquan Bay National Wildlife Refuge. At least once a season, I manage to get a shot like this when a cooperative dragonfly lets me get close. I captured the image below with my trusty Tamron 180mm macro lens on my Canon 50D DSLR. This lens, which has a longer focal length than most macro lenses, gives me some stand-off distance so I can get a macro shot like this without actually being on top of the subject. The only downside to the lens is that it has no built-in image stabilization, so I have to pay extra attention to remaining steady when shooting with it—I generally use a monopod to help reduce camera shake and I think it helped for this image.

The image is framed just as I saw it in my viewfinder. Most of the time I end up cropping my images as part of my normal post-processing, but in this case it looked pretty good without any cropping whatsoever.

Great Blue Skimmer

© Michael Q. Powell. All rights reserved

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“Make sure the eyes are in focus.” I can’t even count the number of times that I have read or heard these words of advice, which I usually try to follow, even when taking extreme close-up macro shots.

These are the compound eyes of the Autumn Medowhawk dragonfly (Sympetrum vicinum), a close relative of the Blue-faced Meadowhawk that I have featured in several postings recently. I took this shot on a cool day when the dragonfly was perched on a tree, trying to warm itself in the warmth of the sun. The camera’s aperture setting was in a middle range at f/9.0, but with the subject this close, the depth of field was pretty shallow and the eyes are pretty much the only portions of the dragonfly in focus (in addition to small section of the wings and the front legs).

autumn_close1_blog

© Michael Q. Powell. All rights reserved.

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