Capturing the night sky with a digital camera is a dichotomy of limits and capabilities.
So much more is revealed when you use a camera than with the eye, because a long exposure allows you to collect a lot more light. It’s an entire world we don’t get to see otherwise. The problem becomes the fact that the stars begin to blur as the Earth rotates (although the effect is sometimes nice).
This was a 10 minute exposure at 16mm, f/4, ISO 100.
Since most Canon SLRs support a long exposure noise reduction feature (which closes the shutter, takes a second exposure, and digitally removes the remaining noise from the original), exposures with this feature actually take twice as long. I can’t imagine doing this kind of stuff back in the days of film cameras, without any kind of immediate feedback.
The faint glow on the bottom right is light pollution coming from Ottawa.
Looking at pictures of stars without context is boring. I was never interested in plain star maps because they’re so abstract compared to nebulas and galaxy shots. I didn’t understand what I was looking at, and I couldn’t possibly appreciate what I was seeing.
Messier 13 — 6 seconds @ f/2.8, 100mm, ISO 3200.
Rated as a Class V globular cluster, which is right in the middle of the Harlow Shapley scale, and the most spectacular type because it’s the best compromise between richness (lower on the scale) and resolvability (higher on the scale).
Take this photo of M13 for example. M13 is a Messier object, which is a catalog of astronomical objects Charles Messier documented to ignore because they resembled comets1, but didn’t follow traditional comet’s paths.
M13 is in the Herculeus constellation. I couldn’t see it but I knew where it was, so I took this shot and zoomed in. On my screen was one fuzzy dot in the middle of a bunch of sharp dots.
This fuzzy dot is actually a huge globular cluster, containing several hundred thousand stars. When I saw it through someone else’s (much bigger and more expensive) telescope, I could see a diffuse haze of white, and resolve dozens of individual stars around it. It was beautiful, like a series of diamonds set on a glowing jewel, and there’s no way I would appreciate a shot of Hercules if I didn’t see M13 like this.
Due to the large concentration of stars in this globular cluster (and proportionally greater possibility of extra-terrestrial life), it was selected as the place to send the first message into outer space.
It’s all these little details that make space so fascinating. These are celestial objects of such vast and incomprehensible sizes, but at the same time, they’re barely seen by the naked eye on a night with even the best of conditions.
- Messier was known as a comet hunter. [↑]
