Readers’ wildlife photos

Reader Don McCrady sent some astronomy pictures; his notes are indented:

I’ve been collecting some astrophotos this summer, and even an astro-video.  To start with, here’s a couple of recent images taken with my astro-rig.

This is the Iris Nebula, part of a vast complex of dust in the constellation of Cepheus.  The central portion shines with the bright blue reflection of the star SAO 19158, the rest of the nebula fading to a dim brown.  This image represents a total of 7 hours of exposure through separate red, green, and blue filters.

Here we have Sharpless 2-132, a very faint nebula in Cepheus, interesting because of the uneven distribution of gases which is evident by the clean separation of colours.  The blue areas are rich in Oxygen-III, while the red areas are rich in Hydrogen-alpha.  This was taken through Hydrogen-alpha and Oxygen-III filters for a total of 8 hours exposure.

For something a bit different, I’ve been experimenting with wide-field astrophotography, which is quite different from the pure technical telescope stuff.  These were all taken with an unmodified Canon 6D and tracked using a Vixen Polarie.

Here is a wide-shot of the Milky way stretching from Cygnus on the left to Sagittarius on the right, taken with a 16mm lens.  It’s difficult to find the bright constellation stars with all the smaller ones that pop out in a long exposure, but the Summer Triangle (Vega, Altair, Deneb) is clearly encompassed in this shot.

Here, Sagittarius and the center of the Milky Way rise above the mountains east of Rattlesnake Lake, Washington.  Several prominent objects are visible around the most prominent object in the center, the M24 star cloud.  Below it and to the right are the Lagoon Nebula and the Trifid Nebula.  Almost directly above M24 are the Swan Nebula and the Eagle Nebula.

The familiar teapot-shaped constellation of Sagittarius will never fully rise above the mountains.

Scorpius rises over the mountains near Rattlesnake Lake, WA.  Rho Ophiuchus and its colourful nebula complex are visible, as is the faint smear of globular cluster M4 right beside Antares, and the vast molecular clouds of the Sagittarius Milky Way are on the left edge of the image.

Finally, here’s a timelapse video consisting of 312 individual images of the Milky Way over Rattlesnake Lake.

I (mis)used the Vixen Polarie (lying flat, not polar aligned) to slowly rotate the camera from east to south at 1/2 the sidereal rate in order to give the timelapse some foreground motion.  I obviously didn’t level it since the end shot ended up crooked.  You can see that at some point while I slept, somebody blithely walked into my shot, totally oblivious with his lights.

Turn the sound on to hear “Lost Frontier”.