Science

High-speed camera system catches close-ups of snowflakes in mid-air

High-speed camera system catch...
The Multi-Angle Snowflake Camera, or MASC, is able to capture 3D photos of individual snowflakes in free-fall
The Multi-Angle Snowflake Camera, or MASC, is able to capture 3D photos of individual snowflakes in free-fall
View 6 Images
These fluffy snowflakes, known as aggregates, form when snow crystals collide with other snow crystals
1/6
These fluffy snowflakes, known as aggregates, form when snow crystals collide with other snow crystals
A collection of snowflakes photographed automatically as they fell at Alta, Utah
2/6
A collection of snowflakes photographed automatically as they fell at Alta, Utah
The Multi-Angle Snowflake Camera, or MASC, is able to capture 3D photos of individual snowflakes in free-fall
3/6
The Multi-Angle Snowflake Camera, or MASC, is able to capture 3D photos of individual snowflakes in free-fall
Tthe Multi-Angle Snowflake Camera, or MASC
4/6
Tthe Multi-Angle Snowflake Camera, or MASC
Each set of three images is a single snowflake viewed from three angles by the Multi-Angle Snowflake Camera
5/6
Each set of three images is a single snowflake viewed from three angles by the Multi-Angle Snowflake Camera
A variety of snowflake types, captured by the Multi-Angle Snowflake Camera
6/6
A variety of snowflake types, captured by the Multi-Angle Snowflake Camera
View gallery - 6 images

Falling snow can play havoc with radar systems, so the more that we know about the manner in which snow falls, the better that those systems can be equipped to compensate for it. That’s why for the past three years, researchers from the University of Utah have been developing a device known as the Multi-Angle Snowflake Camera – or MASC. Using three cameras and two motion sensors, it captures 3D photos of snowflakes in free-fall.

The physical form of a snowflake has a marked effect on how it falls, and it turns out that the super-close-up photos of snowflakes that we’re used to seeing don’t depict what a typical snowflake looks like. According to associate professor of atmospheric sciences Tim Garrett, “These perfectly symmetric, six-sided snowflakes, while beautiful, are exceedingly rare.” They’re usually selected by hand, because their flat shape allows them to sit nicely on a microscope slide.

In reality, however, falling snowflakes accumulate water droplets that freeze onto them, they collide and meld with other snowflakes, and generally form into all sorts of oddball shapes. By photographing whatever passes in front of it in high-resolution 3D, the MASC provides a more accurate overview of what forms snowflakes typically take – it also measures the speed at which they fall past it.

Tthe Multi-Angle Snowflake Camera, or MASC
Tthe Multi-Angle Snowflake Camera, or MASC

The ring-shaped device is roughly one foot (30 cm) wide by four inches (10 cm) tall, and incorporates two 1.2-megapixel cameras and one 5-megapixel camera. When triggered by the top-mounted motion sensor, the three cameras all snap simultaneous images of the flake(s) falling through the ring, from three different angles. The lower motion sensor then detects when those same flakes exit the bottom of the ring, allowing their speed to be calculated.

The MASC cameras take their shots at an aperture of f/5.6 and shutter speeds of up to one 40,000th of a second. Tens of thousands of images can be recorded in one day, although all of the photos are black-and-white, as color filters block some of the light.

Garrett and mechanical engineer Cale Fallgatter are now commercially developing the system through their spin-off company, Fallgatter Technologies. NASA and the U.S. Army provided funding to develop the technology, while the snowflake observation trials were funded by the National Science Foundation.

Sources: University of Utah, Fallgatter Technologies

View gallery - 6 images
1 comment
Fretting Freddy the Ferret pressing the Fret
Every snowflake is very special like you and me. :)