A sharper view of a sharp subject

Click for greater clarity.

In contrast to the soft picture in the last post, compare this one from the same session on November 21, 2011. Here, with a different group of glochids, I used flash as a supplement to natural light; in that way I could stop down (to f/13, as it turned out) and get more of the details of the half-inch disk of glochids in focus. Notice that they have a rough surface, the better to stay in your skin and convince you to stay away the next time you go out wandering in their vicinty. Note also that the two long spines emerging from this areole have a richer redness at their base than the long spines in the previous view.

© 2012 Steven Schwartzman

A soft view of a sharp subject

Click for greater clarity.

Just about everyone is aware that many cacti protect themselves with long, sharp spines. That’s true of the prickly pear, Opuntia engelmannii, by far the most common cactus in central Texas. Especially in the cooler months, the lower portions of its large spines can turn yellowish or even reddish-orange, as shown here. Less well known, and much more insidious, are the short and very slender spines that you see surrounding the base of the large ones. Known as glochids, these tiny spines pull out of the cactus very easily, find their way into your skin just as easily, and don’t come out of that invaded skin at all easily. Once glochided, twice shy, we might say, if we’re willing to customize—cactusize—a familiar proverb.

I took close-up photographs of this prickly pear cactus in my neighborhood on November 21, 2011, and for some of the pictures, including the one you see here, I decided to stay with natural light; that meant using a large aperture of f/4, which in turn meant getting a photograph with only a small portion of its subject in focus. It was a similar approach to the one in the recent photograph of Clematis drummondii, but I applied it to a subject very differently textured from the plumes of the Clematis. The large aperture accounts for the overall soft appearance of today’s image, but some of the glochids are sharp (in both senses), as is the lower length of the prominent large spine, which had turned a rich and appealing red-orange.

© 2012 Steven Schwartzman