May 20th, 2012 Partial Solar Eclipse setting over Colorado Rocky Mountains

Here's a few pictures (and time-lapse video) from the partial Solar Eclipse on May 20th, 2012. It was very tough viewing conditions with lots of clouds and I was hoping to catch a time-lapse of the partially eclipsed sun setting over Longs Peak.

According to the Eclipse Calculator, the Solar Eclipse started at 18:22, and maximum 86% coverage was at 19:29. Using the Photographer's Ephereris, the sunset was scheduled for 20:14 at 297.9° ... but with the mountains, it would be earlier and slightly to the South ... so I setup at the bus stop at Niwot road & 287 - 40.102°N/105.103°W which provided a sight-line of 292.6° with 289° measured on my compass. Turns out when the sun touched the mountains at 19:54 it was slightly North of Longs Peak ... but this turned out to be a good thing because the sun barely came out of the clouds and I would have been skunked if I had been located any further South.

Yea, I'm an engineer, so fun to try to analyze these infrequent events - here's an example with the rising moon. Ironically, my Uncle was a Solar Astronomer and my Dad flew instrument laden planes that "chased" eclipses to extend the totality time.

Photography Notes: Pictures & Video taken with a Canon 7D and 70-200/2.8 with 2x TC attached. I didn't have a strong ND (neutral density) filter to make viewing of the sun safe, so I did a "MacGyver" on my son's eclipse glasses and wedged it into the 2x teleconvertor. So while there was some some light bleeding around my hack job (plus that's not exactly an optical quality filter!), the 10-stop makeshift ND worked quite well. Although in hindsight, the solar eclipse setting over the Colorado Rockies sequence was shot at ISO800, F/5.6, and 1/8s ... so I could have done without the filter ... but would have been worried about damaging my post-cataract eyes and/or the camera sensor. A variable ND filter would have been nice for this shoot.
Irfan was used to add the timestamp on the images and Photoshop CS6 was used to generate a video from the image sequence.

UPDATE: Bob Atkins, who has a great writeup on Astrophotography, pointed out that putting the filter in the rear of the lens (rather than on the front element) is NOT a good idea because of heat build-up ... a bit of a "D'OH!" on my part! Ironically, the sunset sequence was shot at ISO 800, F/5.6, and 1/8s ... so I probably didn't need a filter at that point.

It's a good thing I wasn't tracking the eclipse'd sun when it was higher in the sky (less atmosphere and occulation) for an extended time as I could have had a melted eclipse filter inside my lens ... :-(