2013-01-23

A guide to time-lapse photography

Creating a time-lapse sequence is one of the most rewarding photography projects. Whilst you need a little bit of knowledge to get the best results, the recipe for a great time-lapse only needs a couple of ingredients; foresight and patience.

The biggest ingredient is simply the ability to identify an activity or subject that will lend itself to a time-lapse, and to get set up in advance. Patience is required, not only for the shoot itself, but to persevere in the face of adversity – you’ll probably need a couple of attempts to refine your technique and get the best results. But don’t worry, it’s relatively quick and easy, not to mention inexpensive, and the rewards make it all worthwhile.

What is a time-lapse?
Time-lapse is simply a series of photos taken over a period of time that, when played back as a sequence, appear to fast-forward time. You might think of it as the opposite of slow motion. It’s a brilliant way to examine motion that is normally so subtle that we hardly notice it, like a sunrise or the opening of a flower. You’ve doubtless seen time-lapse sequences on tv, where the actual sequence of events in real time would be far too long to include in the programme. They are a popular staple of nature documentaries, and you might also have seen them in DIY programmes, where a building project is condensed into just a few seconds of footage. There's a great example below of the London Fashion Week stage being prepared at Somerset House in 2010.


Built-in, remote timer or tethered shooting
So how is it done and what do you need to get started? Well, there’s a couple of things you’ll need; namely your camera and either an intervalometer or a computer that will act as one. You’ve probably used the self-timer function on your camera to try and include yourself in the shot. An intervalometer is simply an extension of this in that it will automatically fire the shutter at regular, fixed intervals.

Intervalometer in a D5200
Some compact cameras have these built in, they’re also included in several Nikon DSLR cameras, including the D5100, D5200, D7000, D300s, D600, D800, D800e and D4. Nikon are clearly fans of time-lapse photography as there’s also an intervalometer in the Nikon 1 Series cameras and the Coolpix S30, P510 and P7700 too, to name but a few.

Nikon MC36 Timer
If your camera doesn't have a built in intervalometer, you’ll need to use a remote trigger or use your computer and some simple control software to do the job.

Remote triggers include the Nikon MC36 and the CanonTC-80N3 and Phottix TR-90. It’s possible you've already got the software you need; Canon include a tool on the CD in the box with all their DSLRs called EOS Utility, which will allow you to control the camera via a simple usb cable. 

This is known as tethered shooting, and has the advantage of giving you access to the vast storage space on your computer, so you don’t need to worry about running out of space on your memory card, and you can see the easily monitor the results as they are captured.
Canon's EOS Utility Menu

The software is easy to use; just connect your camera with a usb cable, launch EOS Utility, then choose the Camera Settings/Remote Shooting option. From here, you can make adjustments to your camera settings, when you’re done just click on the stopwatch icon on the right and choose the interval time and number of shots and you’re away.

One final option could be to use the innovative ioShutter that enables you to control the shutter from your iPhone, iPad or iPod touch. The device comprises a release cable and a companion app. There are three versions available, one for Nikon, and two for Canon; one using the N3 fitting used by the 1/5/6/7/20/30/40/50 and 60D, plus another for the E3 connection, used by most of the other EOS models, together with selected Pentax and Samsung cameras.

Regardless of whether you use a built-in intervalometer, a remote trigger or tethered shooting from your computer, the technique remains the same. You simply need to set the interval between shots and the number of shots, which is quick and easy.

Camera Setup
Next you need to set up your camera for the shoot. Having chosen a location it’s best to use a tripod, although you can improvise if you’re indoors, using books to raise your lens above the height of a windowsill, for example.

It’s best to use manual settings for focus, exposure and white balance. This is because the light will almost certainly change during the capture process, with the sun rising or setting, for example, and you want your shots to retain the same look and feel so your sequence looks smooth. In practice this means manually focusing your lens - you can use the magnified view on your camera’s Live View settings to help you. Then adjust your white balance using one of the presets or dial in a custom setting, just avoid using the Auto White Balance setting. Set your ISO to a fairly low level to keep noise to a minimum, 100 or 200 should be perfect, then you’ll just need to set your shutter speed and aperture.

Smoothly Does It
Whilst ordinarily you want your shots to be crisp and details sharp, you might find that the motion and movement in the scenes can look choppy and have a staccato feel when played back as a movie sequence. A sunset won’t look great if it’s jerky, for example, so to avoid this, choose a slowish shutter speed, maybe starting at 1/50th or 1/100th of a second. You’ll then need to adjust the aperture to provide the necessary depth of field to give your shot the look you want. Take a few test shots first to check the exposure, the histogram will help you here,  and make adjustments as necessary. Finally, as with all long exposure shots, you’ll want to cover the eyepiece in your camera to prevent stray light entering into the image. Most DSLR’s have an eyepiece cover on their strap just for this. Simply slide off the eyepiece and slide in the eyepiece cover in its place. You’re almost ready to go.

How many shots will I need and what interval should I use?
Time-lapse is a fairly inexact science, so there’s no real right answer to the question. However, bear in mind that you’re going to capture a sequence of stills and turn them into a movie. The frame-rate for a typical movie will be around 25 frames per second, so if you’ve shot 250 images in your sequence you’ll have a 10 second movie. Likewise if you want to distill a sunrise into a 30 second movie you’ll need 750 shots (30 x 25), for example. If that event lasts 3 hours, then the interval between the shots will need to be 14 seconds to give you the 750 shots you need over that time. For subjects with lots of motion in them that you want to be smooth, such as sunrise and cloud formations, generally you’ll want relatively shorter intervals too, to keep the motion fluid and filmic.  



Don’t worry if you find the calculations complicated, there are lots of handy apps that will help you, Timelapse Helper for iPhone being a good example. You can dial in the interval, numbers of shots and frame-rate and the app will show you the time needed to capture the sequence and also the duration of the finished movie. You can also do this in reverse, choosing the playback time and capture time and having chosen a frame-rate, the app will give the number of shots required together with the interval. Perfect.

Recording Settings
Before recording a time-lapse, you need to give some thought to the files you’re going to capture. The last thing you want to do is run out of space on your card, and whilst image quality is a key consideration, since the images are going to be used as part of a video sequence, and appear for the blink of an eye, you don’t need to record at the highest resolution. Whilst RAW recording with give you complete control over your shots, their size means they are impractical for extended shoots. To maintain a healthy balance between image quality, file size (and hence recording capacity on your memory card), and demands on your computer when assembling the files, large jpeg images will be fine for most situations.

Capture
With the adjustments to the camera made and the required settings dialled into the intervalometer or software package for tethered shooting, you’re all ready to go. Start the shoot, check the first few shots are recording as expected, then you’re free to do something else until the shoot is finished. If you’re outside, just remember not to wander off and abandon your camera. I’m sure many unattended time-lapse cameras have fallen prey to thieves.

Making the movie
Having completed the image capture, the next step is to create the sequence on your computer. Simply copy the files onto your computer, make any adjustments where necessary, and then create the video. One of the best and easiest ways to do this is using Quicktime Pro, which is available from Apple. Open Quicktime and from the File menu select “Open Image Sequence”. Then just navigate to the folder with your timelapse images and select the first one. Hit okay and QuickTime will ask you how many frames-per-second you want your movie to have. For most people 25 frames per second will be perfect, QuickTime will do rest for you.

From here, you can export it for the web or save it so that you can add titles, music and other effects to in a movie editing program. All that remains is to dim the lights, open the popcorn and enjoy your movie.

Don’t be disheartened if your movie isn’t quite what you expected first time. Gladiator wasn’t Ridley Scott’s first attempt at movie making, after all. Just make a note of things to refine and have another go. Practice does indeed make perfect, so keep trying with some short sequences and hone your skills. Just as reminder, here’s a recommended workflow to help you:
  1. Choose your subject.
  2. Work out the number of shots and shooting interval you’ll need. Apps can help you.
  3. Shoot your photographs.
  4. Edit your photos (Optional).
  5. Assemble all your photos together into a video.
  6. Edit your video to add titles and music if required.
 Park Top Tips
  • Plan your shoot
  • Experiment with different shutter speeds and shooting intervals to give your movie the right feel
  • Check out the time-lapses on vimeo and you tube for some inspiration. Sunrise, sunsets, flowers opening, clouds moving across the sky, snow building up on a window ledge, a building or gardening project are all great subjects.
  • Practice makes perfect – if at first you don’t succeed, try, try again.
Jon Penney
Park Cameras

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