Mercury Transit of the Sun Coming May 9, 2016

Venus transit of the sun June 5, 2012

There will a a transit of Mercury across the face of the sun, as seen from earth, on May 9, 2016.  This article on timeanddate.com can tell you when the mercury transit may be available from your location.  It also provides links to information on proper eye protection!

When the planet Venus was scheduled to pass in front of the sun in early June 2012 I wanted to capture the event, but I didn't want to simply record a dark spot in front of a bright one.  So I decided to place earth-bound objects in front of the sun to capture the Sun, Earth and Venus in the same shot.  And why not... the next opportunity to capture a Venus transit across the face of the sun wouldn't come for another 105 years!

My setup for the Venus transit enabled me to shoot it at 400mm:

• Canon EOS 5D Mark III 
• EF 70-200mm f.4 IS L lens 
• 2X III Teleconverter
• Solar film for photographing the sun

Since I was including foreground objects but wanted to catch Venus and the sun as well, depth of field was a concern, so exposures were captured at f/32, 1/500 second, ISO 200.  That's with the solar filter reducing incoming light.

The setup I'm considering for the Mercury transit will enable me to shoot it at 640mm effective:

• Canon EOS 70D 
• EF 70-200mm f.4 IS L lens 
• 2X III Teleconverter
• Solar film for photographing the sun

This time I'll may track the sun and go for a composite photo showing the path of mercury across it.  In that case I could use an f-stop like f/11 to reduce any image softening from diffraction, so something like f/11, 1/2000 second, ISO 100.

Be careful if you try to capture photos of this event.  The sun can fry your sensor, so don't leave the shutter open in live view for long.  

I'm going to go get a camera or two set up and focused now!

"After centuries of trying, only photographic technology could measure the ‘Transit of Venus’ and tell us our position in the solar system." - +Royal Observatory Greenwich

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

---
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.