We hope you’ve found a cool place to set up your Solarcan, and can’t wait to see the solargraphs you create - post and tag ‘em with #SeenOnSolarcan!
To start with, some frequently asked questions:
- Where should I set it up? Any spot with a clear view of the sun will do! For people in the Northern hemisphere, that will mostly mean the pinhole should face south; the opposite for people in the Southern hemisphere. And while most Solarcans are set up in stationary locations, they can also be attached to cars and other moving objects for some wild results.
- How long should I leave it up? That’s up to you! We’ve seen great results with as little as a week’s time, but of course you’ll see more of the Sun’s path the longer you leave the Solarcan up. The sample image below was up for a month.
Pinhole cameras like your Solarcan seem like incredibly simple devices, and they are. But believe it or not, the 2,500 year old technology offers some advantages over traditional, and much more complex, lens-based cameras! In a photographic sense, a pinhole camera can capture an unlimited depth-of-field; so essentially, the entire image is in focus, every time. And because they don’t have lenses that bend light, pinhole cameras often have much less optical distortion than traditional cameras. Pinholes also have an advantage in size; because they don’t require a lens, they can be absolutely tiny, and are easily disguised in other objects - for use in pens, glasses frames, and other James Bond-like gadgets.
Because of those advantages, pinhole cameras lend themselves to some very high-tech scientific endeavours: they’re used inside of tokamak plasma reactors on the bleeding edge of nuclear fusion research, and a few years ago astronomers proposed the New Worlds Imager, a two-spacecraft pinhole camera sitting out in deep space in order to see distant exoplanets.
The New Worlds Imager solves the problem that planets are, of course, much fainter than the stars they orbit, so they’re very hard to see - from a few light years away, the Earth is 10 billion times fainter than the Sun, for example. By putting a “starshade” spacecraft - a giant pinhole camera, with the hole 10 meters across - in front of an existing space telescope, astronomers could block out the parent stars and see thousands of exoplanets directly for the first time.
And what about OUR star? When you look at your solarcan image, what do you see? We’ve provided a helpful guide to interpreting your solargraph below! As an example, let’s start with this picture from a Solarcan mounted right in front of Vsauce HQ:
This photo comes from a Solarcan that was up for a month, starting right around the time of the autumnal equinox. It shows a couple of things you might expect to see on your solargraph image:
- In general, the sun will make a thin arc each day
- Gaps between arcs mean a cloudy day
- Gaps/breaks in the line of an arc are moments of cloudy or overcast weather
- Thicker lines happen closer to the winter and summer solstices, as the sun's path each day changes less, and the arcs overlap with each other. As you can see from our image, closer to the summer solstice, the Sun's path went over and over the same places on the photographic paper, creating a very thick, bold line
- The higher arc lines are closer to the summer solstice, lower ones closer to the winter solstice. The arcs shift between the two as the Solarcan stays mounted.
Here are a few other things you might experience, courtesy of Sam Cornwell, inventor of the Solarcan:
- Ghosting: If the Solarcan moves while it’s mounted - either on purpose or accidentally - you may see a ghost silhouette of the horizon line, or objects in the distance.
- Snail trail: An unusual line that doesn’t follow the same path as the Sun. Their appearance is something of a mystery (even to the Solarcan’s inventor), but they usually seem to occur when it’s moved before or after installation while a bright Sun is present.
- Sparkles: Can appear when there are moving cars in the foreground. Car windows are highly reflective. If a car moves slowly by your Solarcan, it can create little beads of light in the lower half of the image.
- Reflections: The Solarcan will only visibly capture light sources as bright as the Sun. So other reflections you see are usually the Sun’s reflection off cars, windows, or water.
Every Solarcan creates a wholly unique image: latitude, weather, and other factors lead to endless possibilities. We’ve shown you our solargraph - now we’re excited to see YOURS! #SeenOnSolarcan