If you’ve made two time-lapse videos, chances are one was of clouds from your window (the other was you cleaning your living room). I’ve tried to show on this site that time-lapse can be used for everything from macro shots to star trails, but clouds are still the most popular subject.
This is for a good reason; clouds are fascinating in their variations of shapes and color. They’re something we see every day but can’t fully understand and appreciate until we see how they move across the sky without us noticing.
1. Use the Right Interval
Here’s my rule of thumb: if I can see any movement in clouds with my naked eyes, I set the interval to one second or less. For low, fast moving clouds or fog, experiment with faster times. For wide angle shots of slow moving clouds, try about one photo every three seconds.
This all depends, of course, on the final frame rate and desired results. At 30 fps, three second intervals will mean about a minute and a half of movement is shown in every second of footage. This should provide a very dynamic video. A cloud video meant to be serene should use a shorter interval.
2. Know When to Drag the Shutter
I usually recommend dragging the shutter, which just means taking longer exposures to minimize gaps between shots while providing smoother playback. However, with clouds you might want to take shorter exposures. If you’re trying to capture sharp edges on a large cumulus cloud, dragging the shutter could add too much blur. That said, shorter exposures will cause choppier playback if you don’t use an adequately fast interval between shots.
3. Consider a Polarizing Filter
A polarizing filter darkens a blue sky and brings out more color while keeping clouds unchanged. Because of this, clouds appear more vivid against the sky. I almost always try a polarizing filter on landscape and sky photos to see if I like the effect. Some landscape photographers rarely take photos without a polarizing filter.
As with any polarized photography, cloud time-lapse videos will have a stronger effect when the camera is positioned at a 90 degree angle from the sun. This can cause problems if you’re shooting with a wide lens because the sky’s saturation and darkness will vary if you capture too wide of an angle or use a strong filter.
4. Pay Attention to Wind Direction
We’re often at the mercy of wind direction because we can’t change the camera angle. Those times when you have more flexibility, consider the direction the clouds are moving and how you want the final video to look. Also notice that surface wind might not be a perfect indicator of higher wind.
If you watch a few cloud time-lapse videos, you’ll notice different directions give different feelings. Wide angles with sideways moving clouds are very peaceful, while clouds coming toward the camera are more exciting… well, they’re about as exciting as clouds can be, I suppose.
5. Avoid Dust Spots
History lesson time–When I began doing photography way back in the late 1990s, I’d develop my film by swirling it in a mixture of chemicals and then hang it to dry. When it was dry, I’d take it to a light box and look at it through a magnifying glass. Every so often, I’d start yelling at this point because there would be little round discolorations caused by air bubbles in the development process.
Digital photography didn’t get rid of these problems, it just changed them. Now these spots are caused by dust on the camera’s sensor. I won’t go into detail on cleaning sensors because most pros would be terrified of my process. Instead, let me just warn you that nothing brings out dust spots like a bright sky. And nothing is harder to correct than dust spots on hundreds of photos of clouds.
My usual solution for dust spots in time-lapse is to use the heal tool in Lightroom or the patch tool in Photoshop. Because clouds change so rapidly, any auto correct will be obvious. Instead, avoid the problem by taking a test shot of a clear patch of sky. Adjusting the f-stop to the highest number should exaggerate the problem and show you exactly what you’ve got on your sensor. If there’s only one spot toward the side, consider framing for a post crop. If the dust is small, try using a low f-stop. And of course, if you have the time, money, and ability, there are several camera cleaning kits available. If you’re worried about harming your camera, some camera shops offer this as a service but will charge for it.