What the Heck is a Moonbow?

A few years ago when I was really starting to get into digital photography, I was looking through a list of photography workshops being offered, and one of them struck me as being particularly interesting: students were going to photograph a “Moonbow” in Yosemite National Park. Well, that sounds pretty cool! What the heck is a moonbow? Well, as you probably have guessed, it’s a rainbow created by the moon. This particular one would involve a full moon and the mist from the heavy spring flow of Yosemite Falls.

I hadn’t been to Yosemite since I was four (and remember absolutely nothing, not even careening down the mountain in the dark in low gear with smoking brakes), and I hadn’t done any digital night photography yet, so why not? I signed up and booked a flight to Cali. (Apparently this nickname upsets some locals. Too bad.)

The workshop company, Y Explore Yosemite (interesting name), is literally a mom-and-pop operation run by some really nice folks, John and Catherine DeGrazio. They sent me a list of gear to bring for the shoot that essentially boiled down to this: 1) rain gear for me, and 2) rain gear for my camera. Expect to get wet. And cold. And tired.

My instructions said to meet at the Yosemite Falls bus stop at 10 PM. Hmmm. Sounds like a good place to do a drug deal, doesn’t it? So I met my instructor, John Sensor (great name for a digital photographer, I think), and my instructor-in-training, and not one other student. Talk about a teacher to student ratio! Anyway, we started going over our checklist. The plan was to get all of the camera settings adjusted under the light of the bus shelter before heading down the trail in the dark. Sure, we had headlamps, but it was easier to work out the details ahead of time.

John, it seems, has been shooting moonbows for decades, going all the way back to the film days if you can believe that, so he pretty much had the settings figured out. I heeded his technical advice, and then we headed down the trail.

If you’ve never done any night or sunrise photography at popular sites, the etiquette practiced by fellow photographers might not occur to you. It turns out that one thing we generally anticipate is that other photographers might already be there making an exposure that a headlamp or flashlight could ruin. So as we neared the viewing platform, we turned off our headlamps and walked up by moonlight.

We set up our tripods and waited for the moon to rise high enough to illuminate the mist at the bottom of the falls. I had on rain gear and layers of warm clothes, knowing I would just be standing there for several hours. The camera was wearing a large clear plastic bag called a “Rain Sleeve”, with a UV filter on the front to protect the front lens element as well. The plan was simple: keep a towel over the camera until a moonbow appeared, then remove the towel and take a 20 second exposure. Wipe the mist off the filter with a lens cloth, replace the towel, and repeat.

Early on, we had a large number of tourists out there taking flash pictures of the rainbow with their point-and-shoot cameras. What can I say? But eventually they got bored and headed back to the lodge, and the serious photographers were left in peace.

The Rain Sleeve did a fantastic job of keeping my camera dry. Unfortunately, since we had arrived in the dark and I couldn’t really see how far back the mist was reaching, it seems I left my camera bag a bit too close to the falls – it was soaking wet! Oh well, at least nothing was damaged.

We stayed out until about 1:30 AM, when the moonbow fell below the bottom of the falls. I enjoyed the workshop and don’t think I did too badly for a first try. I have since returned to Yosemite three more times to shoot during different seasons and locations. Yosemite is beautiful any time of year, and well worth a visit if you’ve never been. One thing is certain – I’ll be back again!