I’m spending this weekend at the Jasper Dark Sky Festival. The festival itself comprises astronomy talks and star gazing opportunities with some of Canada’s best known astronomers, personalities and photographers. So far the weather has been amazing with warm temperatures and very clear although somewhat cold conditions in the evenings.
The Canadian Rockies are dark and owing to the fact that only about 5,000 folks live in Jasper National Park there are many areas to explore with incredible vistas and no light pollution. It’s very easy to forget how dark the skies can be when most of us live in urban and rural development areas where no thought has been put into the whole concept of light pollution. Fortunately Jasper doesn’t fit into that crowd.
A few of us brave souls (photographers and writers) headed down to the Columbia Icefield late last night. Located about 1 hour south of Jasper township this high elevation area is dark and as expected the sky views were stunning. This is the first time I have used my Nikon D800 for this type of work but having viewed the work of a number of photographers (including talented Yuichi Takasaka who joined us for the trip) I had high expectations. I wasn’t disappointed with the results but did learn many little tricks that will make tonight’s late night foray even better.
What did I learn? While the actual use of the camera in regards to exposure, iso settings and the like seemed like second nature I had an incredibly hard time focusing. The easy solution is to rack the lens over to the infinity setting but this didn’t work. I should have expected this knowing most lenses focus beyond infinity to compensate for movement of the optical elements due to temperature fluctuations. I really didn’t expect this with my wide angles however as I’ve always thought of this as more of a “long lens” problem. Was I ever wrong. Both my Nikon 24-70mm and Sigma 15mm both seem to focus beyond infinity. The easy solution of course would be to use live view although in the dark circumstances the Nikon D800 seemed to have a hard time with this. I resorted to shooting an image, viewing it and making a few corrections until I had focus pinpointed. This is not efficient however.
Tonight I’ll be making notes of where the infinity focus is on my lenses before dark and I’ll perhaps even tape them into that position and see if that helps. I have lots to learn!
Another aspect of doing this type of photography is as the earth rotates the stars move across the sky. While this produces these wonderful star trail images that are so cool (see Yuichi Takasaka’s web site) in many photographs we want to have the stars appear as points rather than dashes. My guess of a 20 second exposure with a 24mm lens worked well for this. A number of the other photographers had tracking devices on their tripods that alleviate this problem. It’s only more equipment and more money.
We are heading out again tonight for another go at astro photography, this time at Lake Annette. I’ll be better prepared, especially in the clothing department. Stay tuned!