Mokka mit Schlag » 2009 » March

By the time we left the California Overland Tour, the sun was setting; but we decided to drive through town on the way back to the hotel. (Not a lot else to do in Borrego Springs after dark.) Beth spotted a church off in the distance, and wanted to check it out. In fact, she spotted several. About four are lined up in a row along Church Lane. However we parked at the Episcopal Church and walked around a bit. House Finches and Lesser Goldfinches were both present in some small abundance.

As Beth was checking out the labyrinth, I was walking around the other side of thee church and spotted another small bird in the back of a small but bushy tree. I thought it was just another finch, but after putting my binoculars on it, I decided it was something else. A kinglet maybe, or perhaps a Gnatcatcher. A Gnatcatcher out here could well be a Black-tailed Gnatcatcher, which would be a life bird for me. So I’m looking closely at the tail, trying to figure out if it’s more white or dark underneath, all the while the bird is moving around in the back of a tree I can barely see in the fading light.

Then all of a sudden the bird turns into my field of view, and I’m looking at its head instead of its tail. Damned if the head isn’t yellow. Gnatcatchers don’t have yellow heads, but Verdins do. The bird flies off, and the light was far too gone to hope for a photo, even if it had stayed. However, the yellow head is pretty distinctive, #463, Verdin.

The next morning we did find several more Verdins at the Anza-Borrego Desert State Park Visitors center, this time in light good enough for a photo. Here’s one:

However the lifer was at St. Barnabas Church.

Allegedly my Tamron zoom lens has a 1:3 macro capability. That is, at maximum telephoto and minimum focusing distance (0.49 meters) objects should be imaged on the sensor at 1/3 their actual size. Let’s check that out.

The sensor in a Canon EOS 50D is 22.3mm by 14.9mm. A U.S. quarter has a a diameter of 24.26 mm. I extend the lens to 300mm and switch it to manual focus. Then I set the focus on the lens to 0.49m (the minimum). I move the camera until the quarter comes into focus and snap.

At 1:3 the quarter should occupy 24.26/3 mm == 8.087 mm. 8.087 mm/ 22.3mm = 0.36, just a tad more than a third the width of the picture. Actually it could be a little smaller than that if I didn’t shoot it head on. The raw image is 4752 pixels wide, so the quarter should be about 1710 pixels wide. Let’s open it up in Photoshop and find out.
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The moths are starting to wake up from the brief Southern California winter (Actually, some never went to sleep, but they didn’t make good pictures.) so let’s see what’s on the memory card. First up we have a beautiful Unciella primula from the Tamarisk Grove Campground in the Anza-Borrego Desert State Park:

Unciella primula – Hodges#10111

This seems to be a little known and perhaps uncommon species. This was BugGuide’s first record, and the first live image for the Moth Photographers Group. I have not been able to find much information about it. Butterflies and moths of North America doesn’t list any records. It is in the California Moth Specimens Database under its previous name, Oncocnemis primula.

Great Blue Heron, Ardea herodias
San Joaquin Wildlife Sanctuary, 2009-03-08