Tuesday, October 19, 2010

Photographing the International Space Station

Ever since my curiosity led me to try photographing the International Space Station as it flew overhead one evening in June, I've had the desire for closer images with more detail than I got on my first attempt. Using the NASA website, it's easy to tell exactly when the ISS fill fly over any location you enter, and NASA's "skywatch" program calculates the times when it will actually be visible.  These are always in times of darkness, or in the early morning or late evening when light from the sun illuminates the space station in the dark sky.  Usually the biggest deal breaker to getting photos is the weather.  You need a clear sky with few clouds or ideally no clouds to get in the way.

This morning was one of the best opportunities yet for photography.  At it's closest point, the ISS was only going to be 221 miles overhead at exactly 6:44:52am.  It would come into view from the Northwest about 800 miles away, and be visible to the naked eye a little over 2 minutes prior to passing at its closest distance.  After passing almost directly overhead (89 degrees from my location) it would be visible for another 2 minutes or so as it sped away toward the Southeast. 

This morning I slept through my alarm and luckily got outside with my camera gear just in time to see it approaching.  Usually I find the moon and set my camera focus on it to get a good 'infinity' focus setting, and then switch to manual focus to shoot the ISS, being careful not to touch the focus ring on my 500mm lens.  Today I was rushed and there was no moon in sight so I had to use autofocus and hope for the best. 
Looking through a long lens and teleconverter at high magnification, it is difficult to even find the bright dot streaking across the dark sky, even though it is clearly visible to the naked eye.   And trying to get the camera to auto-focus on it under these conditions is iffy at best.

This morning I managed to get photos of the space station approaching, but unfortunately I lost it after it got closer than 270 miles away. When I found it again through the lens, I shot more photos as it sped away, but none of them were properly focused.   The solar arrays are clearly visible in the images of the ISS approaching but still not as close as I had hoped, since I was unable to get a shot of it when it was at its closest distance. 

(Click on the image below to see a full size composite showing 7 images of the ISS as it passed over this morning)

Distances listed in the image are calculated using tables from NASA's skywatch program, and interpolating the distances between the 20 second intervals listed.  Before doing this, I synchronized the time setting in my camera with an atomic clock to be sure time time stamp on each image was accurate.  This allowed me to determine the distance in each photo referencing the NASA charts.   You can clearly see that each successive image of the international space station is slightly larger than the previous one, since it is getting closer in each frame.   Even though it is difficult to keep the ISS in the viewfinder even at 1000 mm, I have pretty much decided that I need to stack teleconverters to get even more magnification if I ever hope to get a closer shot.  This will make it even more difficult to find in the viewfinder, but if I succeed the image will be 40% larger.

Friday, October 15, 2010

Camping in Denali National Park

Photographing Mt McKinley

Sunrise on Mt. McKinley - From Reflection Pond, Denali National Park
The highlight of my last few days in Alaska this year was camping at Wonder Lake, which is only 23 miles from Mt. McKinley.  We had driven almost all night to return to Denali from Seward, and this bought me a extra day since we had planned for Monday to be a travel day.  Arriving back in Denali in the early morning, we found that there was space available on the 2pm camper bus, so we unpacked our camping gear and dried out our tents, then repacked for Wonder Lake.  Since it rained the last day at Brooks Falls we had been forced to pack our tents wet before getting on a float plane to fly out.  We went for a good lunch before hopping on the bus. 

Panorama from Eielson Visitor Center - [Click to enlarge]

Wonder Lake is located at mile post 88 on the Denali Park Road - about 6 hours from the park entrance.  On a clear day there is breathtaking scenery along the way, especially at polychrome pass and at Eielsen Visitor Center. 

Our tents set up near Wonder Lake - Denali National Park
Upon arrival at Wonder Lake, we set up our tents and then cooked dinner before getting ready to hike up to Reflection pond to photograph the mountain.  We did not know it yet, but we were in for a special treat.   We heard there had not been a clear day there in the previous 3 weeks.  But we had arrived to a blue sky with a few puffy clouds that moved out during the evening leaving a clear view of Mt McKinley.  Our hope was to get photos with the reflections in the water.

The hike to the pond is about 2.5 miles, and it's mostly uphill.  We set out for the pond, carrying only minimal camera gear.  The bugs were pretty bad so we wore mosquito nets to keep them off our faces.   We arrived at the pond a little before 10pm, a good hour prior to sunset.  While we were at the pond, several others arrived, all with their cameras.  Most folks marvelled at the view, and I was no exception.   It is a rare sight to see the top of McKinley because it is usually shrouded by clouds.  Today it was clear and the lake that stood in front of us was icing on the cake.   We shot lots of photos and made plans to return around 4:30am to do it again when the light from the sunrise would first start hitting the top of the mountain.

Denali before sunset (10:24pm)

We arrived back at our tents around midnight planned to get back up at 3am.  We would need to take up camp and pack all our gear in the morning, before we could hike back up to the pond.  The hike had taken just short of an hour so we needed to budget at least that much time for the morning, since we would be carrying 40+ lbs of gear in each of our backpacks. 

In the morning the sky was clear, so we packed up our camping gear and left it at the bus pickup point and started out for the pond.  All went as planned, and we arrived at the pond at 4:30am.  We shot various photos of the mountain and had plenty of time to plan prior to the 5:08am sunrise.

We were fortunate that there was not much wind and this resulted on few ripples in the water to spoil the reflection.  I shot lots of photos, but my favorite one is the first one at the top of this post.  It was shot at 5:13am, just 5 minutes after the sunlight began to hit the top of the mountain.   It is repeated again below to show the progression from dark to light.

Pre-dawn McKinley (4:30am)

Just before Sunrise (5:01am)

Five minutes after sunrise (5:13am)

We started making our way back to the bus stop at 5:30am in order to catch the 6:30 bus.  Along the way, I couldn't resist photographing this scene, with the lush green meadow in the foreground and the mountain as a backdrop.

Denali through the meadow

We were back waiting for the bus with time to spare, and were able to relax on the long bus ride back.  I was really tired but it was well worth it.

This last photo was taken by a passerby on Monday evening. I'm the guy on the right, and the other guy is my friend, Ken Conger.   Ken is a park ranger at Denali National Park and he has captured amazing wildlife images all around Alaska and elsewhere.  You can see his website HERE.