Sunday, September 27, 2015

See the Supermoon Total Lunar Eclipse Tonight!

Lunar Eclipse April 4, 2015
September 27, 2015, 6 pm -  See the "supermoon" total eclipse tonight!  For watchers in the Rocky Mountain states, partial eclipse begins at 7:11 pm local time, so look outside now!

For those of us on the West Coast of North America, moon rise occurs closer to sunset, in a little over 30 minutes.  Here in the Eastern Sierra, local moon rise is around 6:44 pm and sunset is around 6:47 pm, depending upon how far north or south you are. The moon will clear the horizon to the east right around sunset, well into its partial eclipse phase, and be fully eclipsed from 7:11 - 8:23 pm. Then as the moon exits total eclipse, it will be in a partial eclipse for over an hour more.

For more specific eclipse phase timing in your region, see the article at www.timeanddate.com/eclipse/lunar/2015-september-28

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Photography notes from the April 5, 2015 lunar eclipse:

Lunar eclipses are a fun challenge, in part because they push the limits of your equipment.  The image above was captured at 4:51 am during the April 4 lunar eclipse this year, about 6-7 minutes before totality, so there was a sliver of bright sunlight on the moon.

The Canon EF 70-200 f/4 IS lens was well focused, but shooting any lens at it's maximum aperture tends to result in slightly less sharp images.  Adding more glass elements such as the 2X teleconverter further challenges sharpness.  Adding a teleconverter also reduces the f-stop, in this case 2X to f/8.  I wanted to stay at or below below 1 second exposure time to reduce motion blur, and at ISO 1600 I could use 0.6 second.  The high ISO also creates a little bit of noise, which can also challenge fine detail.

I had changed my shooting location when the weather forecast made the original ones I had identified look less attractive with below freezing temperatures, high winds, and possible clouds to obscure the eclipse.  I decided to just catch what i could from home.  I was shooting a time-lapse sequence, and shooting at 400mm I had room to lengthen the exposure time as the moon darkened, but  and the moon set just before totality.

I had my Canon 70D with a Canon EF 70-300mm f/4-5.6 lens on a star-tracking mount to capture a time-lapse of the eclipse progress without the moon moving out of the field of view.  at 300mm the effective focal length was 480mm, but shooting wide open at f/5.6 that lens was a little softer than the EF 70-200mm and 2X teleconverter combo, even with the moon's relative motion taken out of the equation.

I was basically using the 5D Mark III to measure and track exposure as the eclipse progressed and the moon illumination constantly changed.

The 70D / 70-300mm combo is a lot lighter than the 5Dmkiii / 70-200mm / 2X combo.  Heavier camera bodies and longer, heavier lenses can sometimes cause various problems with sky tracking mounts, but it may be worthwhile to test the 5Dmkiii /70-200mm / 2X setup on the sky tracker and backing off of the maximum aperture and a stop or two on the ISO to get more sharpness and less noise, lengthening the exposure time.

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