OK, raise your hand if this has happened to you. You’re sitting around on your deck or maybe you’re inside doing something, and suddenly you notice through the trees or through your front window that the moon has just come up, and it’s HUGE. The scenery around the moon is picturesque–maybe it’s beautiful trees still lit by the last light from the sunset. Or maybe it’s the skyline of the city where you live. Wow, you think, that would make an awesome picture. You grab your DSLR and go outside to find the perfect vantage point. You frame your shot, take the picture, and viola! A tiny, featureless, glowing ball of overexposed light. Frustrated, you spot meter the moon and adjust your camera’s settings. Now you have a shot where you can actually see a couple of craters, but everything around the moon is pitch black.
Obviously, there’s a secret or two to getting great shots of the moon. I’m going to tell you what they are.
[Top image June 2013 Supermoon rising by Flickr user n.pantazis]
Lenses and the Moon Illusion
It’s quite likely that in some of those failed moon shots of yours you’ve been annoyed by how tiny that moon looked compared to the one that appeared before you in all its enormous glory. Part of the reason for this is the “moon illusion” phenomenon, which is a little bit like one of those optical illusions you used to look at as a kid–you know, the two lines that look like they’re different sizes but are actually exactly the same size. The “moon illusion” is a trick our eyes play on us where the moon appears to be larger when it is just above the horizon than it does when it is further up in the sky. So while you’re thinking, “wow, the moon is huge tonight” your camera is thinking “wow, the moon is puny tonight.” And that’s part of why those photos end up being a disappointment.
The solution to this problem is in your lens. A wide angle lens or even a pretty basic 50mm lens is going to make that moon look tiny. What you need to recreate the moon as it appears to your eye is a good telephoto lens – 200mm is a good place to start, but depending on your goal you really can’t have a lens that is too long. Even at 300mm the moon is still only going to fill 10% of your frame. You can of course crop in post-processing, but to really get some good detail in your photo you may want to consider investing in a good teleconverter.
Other required equipment
Besides that telephoto lens, you will also need a tripod, especially if you are shooting your subject at twilight or at night. And along with that goes a cable or remote release, though your camera’s timer will also do in a pinch. Remember that you’ve got a lot of things working against you with moon photography – as discussed above, you need a very long lens. Set a small ISO to prevent the noise that can become a problem when shooting at night, so you’ll also need a much longer shutter speed.
Remember this basic rule: you shouldn’t handhold your camera if the denominator of your shutter speed is smaller than the focal length of your lens. For example, if your lens is 300mm, you should avoid handholding your camera at shutter speeds slower than 1/300. Most of the time, this is going to mean you’ll need that tripod for your moon shots. And just to make sure you’ve covered all your bases, you should also consider using your camera’s mirror lock-up feature (if it has one). The mirror in your DSLR is what allows you to view the scene through your viewfinder–during normal operations, the mirror flips up out of the way so the camera can make the exposure. This can create vibration during long exposures. What mirror lock-up does is get that mirror out of the way first, lock it in place, and then let you decide when to release the shutter. That way the mirror can vibrate to its heart’s content, and when it’s finished you can take the shot and not worry that the vibration will impact the sharpness of your final image.
When you’re photographing the moon, think manual. Manual everything. You’ll need to use manual focus and manual shutter/aperture. If you’re shooting at night, remember that noise can become a problem, even if you’re using a modern DSLR with a good high ISO capability. For this reason, you always want to photograph the moon at the lowest ISO that your camera allows. Remember too that this is a tricky lighting situation no matter how you approach it, so bracket every shot you take to give yourself the best chances at getting the best exposure.
How do I expose for the moon and for the rest of the scenery after then sun has gone down?
Well the quick answer to that is, you don’t. Shooting the moon at night is like shooting directly into any other very bright light source with a camera. Matrix or evaluative metering has a very hard time figuring out what to do with that bright moon in its relatively dimly-lit scenery, and it will end up overexposing the moon every single time. But you can’t just spot meter the moon either, or you’ll end up with a perfectly exposed moon on a black background, with no details at all in any of the scenery.
Hobby photographers are often stumped by this, because the moon just doesn’t look like it’s that bright to the naked eye. That’s because our eyes are much better at adjusting to the moon’s brightness in comparison to the rest of a scene than our cameras are. So no matter how hard you try or what settings you use, you’re not going to get well-exposed scenery and a well-exposed moon in the same shot after the light from the sun is gone. So how is it done, then?
The trick of course is to take two shots, and merge them in post processing. In the first shot, expose for the moon and in the second, expose for the scenery. To capture those details on the surface of the moon, spot metering is going to be your best bet. Again, it’s always best to bracket your moon shots, check the results on your LCD and then reshoot if necessary.
Once you get a good shot of the moon itself, meter for the scenery and bracket until you get an exposure you’re happy with.
Then in post processing, mask out the over-exposed moon from the second shot, and replace it with the well-exposed moon from the first.
What if you want a lot of scenery in the shot but you want to moon to seem bigger? You will need to use a wide-angle lens to shoot the scenery and a telephoto lens to shoot the moon. Again, a skillful merge in post-processing should produce the results you’re looking for.
Shoot the moon during the day
During the day, the moon is competing with the sun, so you aren’t going to have the same exposure problems. If you’re lucky and the conditions are right, you can also capture the moon at twilight while still keeping much of the environment well-exposed. But bear in mind that the window for good twilight moon shots is a short one, and you’ll probably have better luck making composites than you will in capturing a good single shot of the moon at this time of day.
Shoot the moon on a clear night
You can get some interesting shots of moonlit clouds on a partly-cloudy night, but you won’t get a great shot of the details on the moon itself unless the area around it is cloud-free. This goes for pollution, too –that same yucky stuff that hangs on the horizon during the day is going to prevent you from getting a clear shot of the moon at night. If the moon itself is either your subject or an important part of the scene, you’ll need to make sure you’re in a location that is free of air pollution. And as long as you’re traveling anyway, choose a destination that is in the higher elevations. Higher elevations mean there is less distance between you and your subject, which also means there is less atmospheric haze between you and your subject.
Photographing the moon as an isolated subject
With the right equipment, it’s actually much easier to photograph the moon as an isolated subject than it is to photograph the moon within a landscape. But you do need that super long lens (400mm or higher) – and unless you also have a telescope and a camera mount to go with it, you’ll still have to crop your final image.
Now, the moon is quite a long way away so when you’re shooting it as an isolated subject you don’t need to have a closed aperture to get it all in focus. So choose an open aperture – a low f-number like f/5.6 – to let the most light in. Your shutter speed, of course, is going to depend on your spot meter, and bracketing – but don’t forget that the moon is a moving object. When you are shooting it with a very long lens, you might actually get some motion blur at slow shutter speeds. You don’t really want to go much below 1/100 if you can avoid it. This of course is variable depending on the focal length of your lens, but some experimentation is always in order.
Whether you’re shooting the moon as a lone subject or including it as part of the scenery, you will still need to do some work in post-processing. Because you used your spot meter to capture the moon itself, you may find that it looks too flat or too gray (remember that your spot meter assumes that the object you’re pointing it at is a middle gray, and it will expose with that in mind). You may need to do some slight contrast adjustment to bring out some highlights on the surface of the moon. Your image may even benefit from a little sharpening.
Speaking of bracketing, you may find that none of your exposures are exactly what you want, especially when shooting the moon as a lone subject. Some parts of the moon may be overexposed and other parts underexposed. If this is the case, try merging the images into a single HDR image.
If you’re having trouble getting a good exposure at the aperture you want, consider using a one or two stop neutral density filter to cut back on the amount of light that reaches your sensor. Having one of these filters on hand will give you a lot more flexibility in getting the shot you want. Alternately, you can also use a polarizing filter–during the day a polarizer can be particularly useful , because it will darken a blue sky while also bringing out some of those details in the moon’s surface.
Shots of the moon as a lone subject are fun to experiment with and a good exercise in technical know-how, but don’t forget that they have been done … and done … and done. While fun to add to your personal portfolio the shots that are really going to impress will be those that include scenery. So master those lone-moon shots and then move on to the more challenging stuff–an amazing composite of a moonlit landscape with a beautifully exposed moon just above it.