One of the many photographs former Microsoft CTO Nathan Myhrvold has taken of snowflakes.
Why would former Microsoft chief technology officer Nathan Myhrvold spend a year and a half building a custom 100-megapixel carbon-fiber super-cooled sapphire-lensed LED-lit super camera to take pictures of snowflakes?
Because he can.
Because he wanted to.
And ... because snowflakes are much more important than we give them credit for.
“Snowflakes are something that we don’t think of as food, yet most of us in North America anyway, spend our whole summer drinking melted snowflakes, right?” Nathan Myhrvold told me on a recent episode of the TechFirst podcast. “Without snowflakes, we would have no water. It is the form of snow that allows us to meter it out over a period of many months.”
But most likely, just because it’s cool.
Myhrvold is not just the former CTO of Microsoft. He’s the author of multiple cookbooks detailing the art and science of cooking. He worked with Stephen Hawking on quantum theories of gravitation. He’s published peer-reviewed research on subjects as diverse as paleontology, climate science, and astronomy, and is currently working on a massive multi-gigapixel picture of the Milky Way galaxy.
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(170,000 frames and counting, for that.)
And he’s been interested in photograph for a long time.
“When I was a kid, I saw pictures of snowflakes ... these beautiful faceted crystals, almost like gems but more fragile than gems,” Myhrvold told me. “As I got older, I sort of learned why they look that way. I also became a photographer and I started taking pictures of food and of landscapes.”
It turns out that taking pictures of snowflakes is hard.
Really hard.
Listen to the interview behind this story in the TechFirst podcast:
Sure, there’s the obvious problem: melting. But snowflakes don’t just melt. They also sublimate, which is the direct transformation from a solid (ice) to a gaseous state without passing through the liquid water stage. And they can accrete: adding mass from atmospheric moisture. Plus, they’re small, they’re largely transparent, and the kind of light that you typically use to photograph things would actually melt them into an unappealing mush. Just to make the whole snowflake photography enterprise more fun, the best weather for finding and photographing them is a fairly frigid minus 15 to 20 Fahrenheit, or minus 26 to 29 Celsius.
So Myhrvold had to invent a camera system that connects to a microscope that can photograph his short-lived fleeting subjects.
Another of Nathan Myhrvold's snowflakes.
The tiny size means that his camera and microscope needed to be able to move closer or farther by just a micron at a time. A micron, or millionth of a meter, is legitimately tiny. Human hairs measure 80 to 100 microns wide, so the motors needed to be amazingly precise with very fine control.
Also, when you’re working in microns and you can’t fully control the temperature, the frame your camera and microscope rest on could contract or expand. You need something very strong and very stable, but you also need something that’s not made of metal that will grow or shrink according to the temperature.
Hence the carbon fiber, built by a company in Vancouver, Canada.
And light matters too.
“We tried using LED lighting, continuous LED lighting, and that just didn’t work,” Myhrvold says. “It was putting too much energy on the snowflake, and that meant it either melted or sublimated way faster than it should. The other problem is when you use continuous light, then you need to use the shutter in your camera. Well, but the problem with having the shutter is then that makes things shake, and that’s not a good thing.”
The solution came from a company in Japan that makes ultra-high-speed pulsing LED lights. Designed for factories that need to take very quick pictures of products on fast assembly lines for quality control, they could emit a pulse as short as a microsecond, one millionth of a second. Benefit one: no significant heat transfer. Benefit two: super-short pulses cancel out any impact from vibration that might be happening in the frame, camera, or microscope assembly.
No two snowflakes are completely alike. Here's another Nathan Myhrvold photo.
Adding to parts from the U.S., Japan, Canada, and doubtless other sources, Myhrvold added cooling: liquid refrigeration units from hyper-clocked gaming PCs. (Note: ordinary car antifreeze has a jello-like consistency at minute 20 degrees: Myhrvold needed a special antifreeze that stays liquid.) He also added artificial sapphire lenses for his camera (”eight times the thermal conductivity of glass,” he says) and a few other arcane elements.
Now he had a camera capable of taking quality snowflake pictures.
All that he needed was snowflakes. That was also a challenge.
“Most ski resorts are in places that are too warm — believe it or not — particularly where they put the accommodations is too warm,” Myhrvold says.
Solution?
Fly up to Alaska, and fly up to northern Canada. Timmins, Ontario apparently has perfect weather for great lake effect snow, plus a surplus of rental cottages with convenient porches. Fairbanks, in Alaska, also works, though it sometimes lacks falling snow even if there is snow on the ground. Alternatively, there is also photogenic snow in Yellowknife, Northwest Territories.
Bring the camera assembly, and start running around in the snow with a black foamcore board. If it’s windier, use a felt-covered board that’s stickier. If necessary, use a tiny paint brush, size triple-zero, build up a bit of static charge on it, and gently move the snowflake into perfect paparazzi position, ideally without touching it.
Then: take pictures.
Former Microsoft CTO Nathan Myhrvold
Each snowflake pictured here is a combination of between 100 to 500 stacked shots. Snowflakes have some depth to them — perhaps 10 microns — so you need to move your camera in and out slightly to capture all the detail in focus. Most trips, Myhrvold says, last three to four days. In that time, he’ll take about 50,000 pictures with his 100-megapixel camera.
The result of all that effort is a few perfect pictures, captured in perhaps 200, 300, or even 500 stacked frames of 100 megapixels: the highest resolution snowflake photographs ever captured.
What’s next?
Possibly 3D.
Myhrvold says he may add a Fanbeam laser that can measure very fine differences in distance, much like a LIDAR sensor in a self-driving car, so that he can 3D print meter-sized versions for each snowflake. That would result in roughly three-foot wide perfect replicas of snowflakes: a potentially spectacular addition to most people’s home or office decor, particularly around Christmas time.
Which only leaves one question: why did Nathan Myhrvold start this quest in the first place? Because he can, and because he wanted to, sure. And yes, because it was cool.
But ultimately, to scratch an itch.
“I’m curious about things,” Myhrvold told me. “So I’m curious about finding things out, and trying to understand something that people don’t. Or trying to understand something that I don’t, you know, acquisition of a new skill, like learning how to deal with these snowflakes … well, that’s a learning thing.”
Which sounds like a great driving motivation for education in general. And the catalyst for an endless series of quests for knowledge ... like the next project: a giant multi-gigapixel mosaic of the Milky Way.
Don’t count on that one being 3D-printable, though.
Get a full transcript of our conversation here.
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