Before dawn this Saturday, December 10th, viewers in the Western U.S. and Canada will be able to see a total lunar eclipse. If you live in the eastern half of the U.S. unfortunately you'll only be able to see a partial eclipse. People in most of Europe, Asia, and Australia will also be able to see a total eclipse, though in Europe it will be visible at moonrise on Saturday evening. This NASA page shows where the eclipse will be visible throughout the world, and this page shows more detail for western North America.
If the weather cooperates, and you want to try make your own eclipse photographs, here are some tips. (I've copied some of this from my post a year ago, but the information about the moon position is all new.)
First, you should move away from cities to avoid light pollution. In western North America, the moon will go into full eclipse as its setting, just before sunrise. To see it you'll have to have a clear view of the horizon to the west-northwest. John Cubit on Calphoto found this link from the Griffith Observatory with an excellent graphic showing the path of the moon.
Because the eclipsed moon will be so low in the sky, this is a great opportunity to include a silhouetted foreground element—trees or buildings, for example. However these objects can't be too tall or they'll just block the moon (a mountain won't work).
I made this photograph by taking separate exposures of the moon, each ten minutes apart, and layering them together in Photoshop. The Photoshop techniques are beyond the scope of a post like this, but the short answer is to use the Shift key when dragging one layer on top of another, so they line up exactly, and use the Screen layer blending mode for all but the bottom layer.
To make a sequence you have to predict the path that the moon will take so you can compose your photograph accordingly. The best tool I’ve found for this is an iPhone app called Star Walk. With this program you can look at a section of virtual sky and then spin the Time dial, allowing you to watch a fast-motion movie of the night sky for any time and place. Very cool stuff. If you don’t have an iPhone there are many other applications and online resources that will allow you to determine the position of the moon, just not with such ease. The best of these is probably The Photographer’s Ephemeris, a free desktop application.
In the field the hardest parts are focusing and getting the right exposure. For tips about focusing, and general suggestions about equipment and techniques for night photography, see this earlier post about photographing lunar rainbows.
Light meters are useless for getting good exposures of the moon itself, which is what we’re talking about here, because even with a one-degree spot you can’t meter off just the moon—you’ll be reading both the moon and surrounding black sky. So here are some suggestions based on past experience, including making the accompanying photograph. All the times and f-stops are for 200 ISO, so you’ll have to adapt for other ISOs:
Full moon, or moon more than half visible: 1/60 sec. at f/16
Half to one-quarter of the moon visible: 1/30 sec. at f/16
Less than one-quarter of the moon visible: 1/15 sec. at f/16
Just the edge of the moon lit: 1 sec. at f/16
Fully eclipsed at beginning and end of totality: 4 sec. at f/5.6
Fully eclipsed, deepest totality: 8 sec. at f/5.6
Keep in mind that you don’t want exposures that are too long, as the moon will move and blur. You can get away with 8 or maybe even 16 seconds with a wide-angle lens, but with a telephoto you probably need to keep exposure times to two seconds or less. Consider pushing up the ISO with telephotos. Bracketing exposures is a good idea.
When making the accompanying photograph I used flash to light-paint the trees in between making exposures of the moon. Light painting is a complex subject that I won’t get into here. If this is the first time you’ve ever tried photographing an eclipse I’d suggest you keep it simple, and don’t try light painting. Just try to capture single images of the moon itself, or perhaps a sequence with silhouetted trees in the foreground. Exposures anywhere from 10 to 30 minutes apart can work for a sequence; just make sure to keep the interval the same throughout. Make sure your tripod is solidly planted before beginning the sequence.
When the moon is full, stars are barely visible. But when the moon becomes totally eclipsed an amazing thing happens: the sky gets dark, and thousands of stars appear. In the accompanying photograph I made an exposure for these stars when the moon was fully eclipsed: 30 seconds at f/4 and 3200 ISO. Anything longer than 30 seconds would have turned the stars into streaks. I then cloned the vastly overexposed moon out of this frame, and added this layer to the mix, using the Shift key and Screen blending mode as described above.
However for this eclipse, since the sky will be lightening with the approaching sunrise, I doubt this many stars will be visible. But this extra bit of light will help silhouetted objects stand out against the sky.
Michael Frye is a professional photographer specializing in landscapes and nature. He is the author and photographer of The Photographer’s Guide to Yosemite, Yosemite Meditations, and Digital Landscape Photography: In the Footsteps of Ansel Adams and the Great Masters, plus the eBook Light & Land: Landscapes in the Digital Darkroom. He has written numerous magazine articles on the art and technique of photography, and his images have been published in over thirty countries around the world. Michael has lived either in or near Yosemite National Park since 1983, currently residing just outside the park in Mariposa, California.