Rainbows are a favorite subject for landscape photographers, but the lesser-known phenomena known as “moonbows” — rainbows created by moonlight — are not as easy to find. Once photographers know where to look, however, they are easier to predict.
California-based photographer Brian Hawkins has been capturing the famous moonbow at Yosemite National Park for 12 years. His obsession with these lunar rainbows started in 2011, well after he first photographed Yosemite.
A mechanical engineer by trade, Hawkins spends his time planning his photographs of rainbows at night in Yosemite by creating 3D simulations. For this spring, Hawkins has identified three optimal windows for capturing the moonbows: April 14 through the 18, May 13 through the 17, and June 11 through the 15.
Hawkins analyzes the data and details the best time to capture moonbows on his website where, in addition, he keeps up to date weather forecasts so photographers can be fully aware of their actual chances of capturing incredible photos.
“Moonbows are simply rainbows which occur at night, using the light of the moon instead of the sun,” Hawkins explains. “They are just as common as daylight rainbows, but they often go unnoticed because human vision is not as sensitive in low light. Moonbows can be found in a predictable source of water spray that gets ample moonlight, such as the enormous waterfalls of Yosemite National Park.”
Hawkins says moonbows can happen anytime moonlight is shining on water droplets in the air at the correct angle relative to an observer.
“In practice, it is easiest to see them when the moon is almost full on a clear night while standing near the mist of a waterfall. I recommend looking when the moon is within two days of being 100% full. If you are lucky enough to capture it, moonbows during a supermoon are even more intense.”
Simply planning to arrive at Yosemite during the dates and times Hawkins has outlined does not guarantee a person is going to see the moonbows, however. Observers will still need ideal conditions in order to photograph the colorful bands above the misting water.
“In addition to a nearly-full moon, clear skies are a must. Even thin clouds can diffuse the moonlight such that a moonbow will not occur. A calm night can also limit the drama of the moonbows, as it is often helpful to have some wind to carry the mist from the waterfall higher in the air. The most important aspect of photographing moonbows is knowing where to position yourself. Moonlight refracts and reflects through water droplets at the ‘rainbow angle’ of 42 degrees, so a photographer has to know where and when to be to achieve that angle relative to the water and moon,” he explains.
“My background in aerospace engineering helped me develop a method for visualizing this using 3D modeling back in 2012, and in 2018 I started sharing this information on a dedicated website, Yosemite Moon Bow, so that others can know when to witness the moonbow at popular locations in Yosemite.”
With over a decade of moonbow experience in Yosemite National Park, Hawkins has become known as the end-all resource for all things moonbow.
“I first photographed moonbows in 2011,” Hawkins says. “I can’t remember how I first heard about it, but I was already enamored with photographing Yosemite and this was just another magical phenomenon that occurs in this special place.”
“The idea for this short film came to me in 2016,” he continues. “I wanted to do something that no one had done before. Others have made moonbow videos using timelapse, but for me, the fast motion never really captured the true experience. So, I wanted to show people what it was really like to witness the moonbows, as our eyes would actually see them. Plus, it doesn’t hurt that I enjoy the technical challenge that this film created. I started capturing these real-time video clips in 2016, and over the years have made two to three visits each spring, except for 2020 when the park was closed.”
Filming real-time video in the darkness of night wasn’t always easy. Until the recent technological advancements in cameras, a film like this would have been impossible.
“The film was shot on Sony mirrorless cameras; primarily the A7S II and more recently, the FX3. I also used a selection of fast prime lenses. High ISOs were needed and significant noise reduction was required in editing,” he says.
“I knew to make this film truly unique, I would have to think outside the box and capture angles that weren’t so well known,” Hawkins continues.
“I experimented with countless angles. Among them were deliberate choices to include people, buildings, cameras, and other light sources to illustrate the nighttime setting. My favorite angle was from Glacier Point. At that far of a distance, careful calculation had to be made regarding when to be there as the moonbow is only present for 15 minutes. I believe I was the first person to photograph the moonbow from Glacier Point. I also really enjoyed hiking the Upper Yosemite Fall trail with my friend from the Ansel Adams Gallery, fellow landscape photographer, Brittany Colt. We had to stay up until 3AM to capture the moonbow composed with Half Dome in the background.”
It is easy to see that the years of research and hard work paid off. Hawkins’ film delivers an incredible view of a rarely captured phenomenon in one of the most photographed locations in the world. Even so, Hawkins will never tire of photographing Yosemite National Park.
“Yosemite is one of those rare places that never seem to run out of ways to challenge and inspire. In addition to my enjoyment of its natural splendor, it also appeals to my passion for science as I research Yosemite’s phenomena such as moonbows. All of this leads to the joy of being able to share my art to show the world how unique and beautiful Yosemite National Park is.”
Image credits: All photos by Brian Hawkins