Milky Way Lightning

Continuing from my last entry, I'm driving across Utah at night trying to reach Natural Bridges National Monument.  Up and down hills with my high beams barely hinting at the terrain, vastly different from Colorado.  A note to others, don't drive through pretty landscapes at night, it negates the entire point.  But, I was exhausted and just wanted to get there and sleep.

I reached the entrance to Natural Bridges around 9pm, and once again, it's a long drive to the visitor's center.  I pulled to the side of the road and took a few pictures off the mesa towards the thunderstorms in the distance.  The Milky Way was just starting to be revealed by the clouds.

I drove up to the visitor's center, long past operating hours.  As I looked for a map to show me the campground, someone exited the front door with a large cylindrical object on wheels.  I initially thought it was the janitor taking out the trash for the day, but it was actually a park ranger taking out a telescope.  Because Natural Bridges has one of the darkest skies in the United States, they have their own portable telescope to use during ranger presentations.  I asked the ranger if he minded me hanging around.  Not only did he not mind, he let me help him set up the telescope and test it!

The telescope was the reflecting variety, so I got to assist aligning and focusing the mirror.  The telescope had a go to feature: once the telescope knew it's location it could automatically aim at objects in the sky.  We used the constellation Cassiopeia and the star Antares to locate the telescope, so now I know where to find Cassiopeia, which can be used to find Polaris.

Once the telescope was set up we took the next half hour looking at various Messier objects.  Charles Messier observed comets in the 18th century and created a list of objects to avoid because they weren't comets.  Ironically these objects turned out to be galaxies, nebulae and clusters, the most popular objects to observe.  I saw Andromeda, a bunch of globular clusters and a nebula.

After my astronomy lesson I drove to the campground.  The distant storm had approached and an interesting composition of the Milky Way over a lightning storm was forming.  I walked away from the campgrounds to set up the camera, using an aperture of f/3.5 and an ISO of 3200-6400 to capture the stars.  Ideally my ISO would be lower, but f/3.5 was the lowest aperture I could use on this lens so I needed to compensate.

I don't have a lightning trigger for the camera, so I was forced to use a full 30 second exposure and hope to catch lightning bolts.  They were frequent enough that it wasn't an issues, I even caught the glows from distant strikes.

In the previous shot you can see that the bolt is blown out and not defined.  This is due to the very high ISO capturing too much light, so I tried a composite shot.  The first photo settings would be the same and would be strictly for the Milky Way.  The second shot, taken immediately after the first still uses an aperture of f/3.5, but I lowered the ISO to around 1600 to capture the bolt clearly.  After post processing, they are combined in Photoshop to take the best of both worlds.  Ta-da.

The storm moved on and I walked back to camp to sleep in the passenger seat of the rental car.  Which was the second most uncomfortable night of sleep on my trip.