Why your photos of the supermoon may not have looked so good

It was the first blood supermoon eclipse in 33 years, but more importantly the first of the era of cheap digital photography and social media sharing.

That combination led to a ton of terrible photos. Not only did Grandma and little Susie snap blurry light speckles, but even Mom and Dad posted photos that looked like the stuff that gets caught in your eye rather than the majestic orb beholden by the eye itself.

It just doesn’t make sense. We could see the moon with our own eyes. It was huge and the texture of the moon’s surface was sandy and elegant.

Our phone cameras have never been better. When we take photographs of mountains in the distance, we can capture their glory, even with a bursting sunset.

So why did our cameras fail us so badly for the supermoon on the horizon?

Although it’s a truism that everyone has a professional camera in their phone, only the photos by professionals with 300mm zoom lenses attached to SLR cameras mounted on tripods captured the amount of detail that our eyes saw.

Part of the reason the camera photos were so bad is that most people shot on automatic settings. If you try to capture that moon against a horizon of city lights, the camera’s sensors are going to choose a setting that brings out more light. The camera thinks that, because it’s nighttime and there isn’t much light coming through, it should increase the light in your photo. But that makes the moon too bright to see its shadowy details.

What you’re really trying to photograph is the surface of the moon and the gradients of shadow that give the moon its texture. (In camera-speak, you want a low ISO like 100, a high/narrow aperture to limit the light coming through like f11, and a pretty fast shutter speed, e.g. 1/125.)

Those settings are perfect for capturing the moon, but not for everything around it. You can’t have both a good picture of the moon’s surface and a picture of the horizon it is nestled in. You have to choose. You can then combine two photos in a photo editing program to make the moon appear in the setting as it did to you on the horizon.

Another reason is that the lens of your camera is different than “the lens” of your eyes. Your eyes are said to be the equivalent of a lens in the 30mm to 50mm range. Your camera on your phone is typically smaller, so the images it captures don’t look as large as what your eyes can see.

But the main reason the photos don’t look so good is because the moon is so far away. Although our smartphone cameras can capture mountains in the distance, they don’t capture specific parts of the mountains with very much detail. A better comparison would be to think of trying to capture the expression on someone’s face on the opposite end of a football field. Your eyes won’t even see it very well, let alone your smartphone camera.

That’s why all the professionals at football games have such long lenses. Those long lenses let in more light, from a narrow range – so instead of capturing the whole scene, it focuses on one small bit, usually farther away. In those cameras, the lens is farther away from the sensor that processes it: That’s why telephoto lenses have really high millimeter numbers, like 200, 300 or 500.

The reason the pros use a tripod is simple. Nobody’s hands are perfectly steady. Even a millimeter of shake at the point of the camera will lead to a lot of wobble where you’re trying to focus. Even pressing the shutter itself, without a remote, can cause too much shake and wobble.

But don’t fret: you have 18 years to practice these tips for the next time a blood supermoon eclipse appears in 2033.

This story was originally published September 28, 2015 at 9:36 AM with the headline "Why your photos of the supermoon may not have looked so good."