Friday, December 19, 2014

Lost And Found!

I take a lot of photos, likely over 10K per year, especially with time lapses and stacking of astronomical images. Most are what I think would make good blog posts, and it is certainly easy to take lots of pictures these days without the cost of film or processing!  At the same time, I find that if I don't get them in the blog queue right away, they get lost under more recent images and get forgotten. 

While walking along the river the other day (we're still in Illinois), a set of IR images I took this summer came to mind.  In infrared wavelengths, water is a good absorber, looking mostly dark in images unless you get a reflection.  The above image shows the Wood effect clearly - very bright vegetation from the trees on the far bank.  But what came to my attention was the light streaks in the water at the bottom.  Turns out the Fox River is very shallow at this point, only about 25cm (10 inches).  What was coming into view was the river equivalent of seaweed or moss, growing in long strings.  Taking longer exposures, it took a couple shots for me to expose long enough for details, shown here at right and left.  It took about 10X the exposure to bring out the white-glow of the underwater plants.  In the shallows the local current carried the sinuous plants downstream, and getting a couple shots with different patterns was easy to do.  It made for interesting patterns, and it is also interesting to see how murkey the water looks due to the water absorbing the IR wavelengths.

Back in August our barrel cactus was in
full bloomin' mode.  While the buds were easy to catch, looking photogenic for several days before popping into flower, by the time I get back from work, they've been open all day and are well-worn from pollinators.  In any case, these pair of images were taken with a macro, with at least 6 frames taken at different focus settings to combine into the final focus-stacked images.  Clicking on the right image you can see how the stigma are wiped clear of pollen on the outward-facing side.

In October, my friend Bob Taylor invited me up for an observing session at the Mount Lemmon SkyCenter.  I'd posted many images, but had taken a series of sky exposures that for some reason weren't up to my standards.  However, as a result, one of the highlights of the all-night session, of the Gegenshein clearing the pre-dawn horizon didn't make it into the blog.  Shown here at left, the conical glow in the sky is not from the rising sun, but rather sunlight reflecting off dust from comets and asteroids in the plane of the solar system.  Following the ecliptic path, it shoots right up towards and engulfing Jupiter, the bright object at upper right.  Visible nearly all year long from a dark sky, it is especially visible in the northern hemisphere in the early Fall morning sky and the early Spring evening sky when the ecliptic makes a large angle to the horizon.  And since I don't like unlabeled star fields, I've included an annotated version at right, including the outline of Mount Graham at lower left, an antenna array at bottom center, and the red-lit antennae 5 miles distant at Mount Bigelow.

So I'm glad I re-discovered these images that hadn't appeared here before.  Certainly worthy of blog-inclusion!

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