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Time-Lapse Photography with the Konica Minolta 5D
Time-lapse photography can turn normally slow and unnoticed activity around us into dynamic and fascinating moving images. It's a tool that has been with us in one form or another for at least a century. I remember seeing many examples of this technique when I was young, in films about scientific subjects like plant growth, insect behavior, and meteorology. Much of what I saw in those days was probably the work of John Ott. His pioneering efforts in filmmaking, and studying the effects of light on organisms, are well documented. This short 1953 article from Time magazine is a good introduction. But the earliest specific use of time-lapse work that I can recall, and that really made an impact on me, was in 1983's Koyaanisqatsi. In that film cinematographer Ron Fricke (with strong assists from composer Philip Glass and director Godfrey Reggio) raised time-lapse photography to the status of art. (Koyaanisqatsi and several other works in the same genre are nicely documented at the Spirit of Baraka website.)
Although the principles and techniques of time-lapse work were first established and refined by dedicated experts using custom-built equipment, the rest of us can now enjoy working this magic ourselves using just about any reasonably versatile digital camera (like the Konica Minolta 5D) and a few additional items. Read on...
Basics to Blockbusters
The basic idea of time-lapse photography was quite simple: on a strip of film, shoot a series of frames of a changing scene at intervals that are much longer than the rate at which the film will be displayed. For example, shooting frames at one second intervals, and then displaying the film at the typical rate of 24 frames per second, will produce a result that appears to move 24 times as fast as the original activity. But within that fundamental premise, the time-lapse photographer must work with all of the same parameters as a still photographer - lighting, composition, focus, aperture, shutter speed, etc. - while also having to select the best frame rate and number of exposures, and predicting how all of these factors might affect successful recording of a changing scene. Maybe not so simple after all!
As the time-lapse experts honed their skills and better equipment was developed, more sophisticated approaches appeared. One major enhancement was the addition of precisely controlled camera movements during the exposure phase. A heightened sense of realism results when the camera itself appears to be moving through the time-lapse scene. More recently, the combination of motion-controlled time-lapse photography and computer-generated images was another advance that opened new doors. Think of the impact that the bullet time sequences of The Matrix made when we first saw them. Many of the scenes created for that film and numerous others (though some are essentially the reverse of time-lapse sequences: shooting a subject from multiple camera angles within a very brief period of time) relied on basic principles established by the early practitioners.
Granted, photography enthusiasts would have some trouble duplicating the bullet-dodging effects of Hollywood productions; but we can still do some surprisingly good stuff with very basic tools. In fact, all that's really required is a camera and a computer, which we already have. But a few other items can help out immensely:
an ordinary tripod
an intervalometer (may be built into the camera or a separate accessory)
an external flash or lighting setup (may be required for certain types of scenes)
and, if you have one, an astronomical telescope tripod with an equatorial drive mechanism
As far as equipment is concerned, that's pretty much it.
What's the Right Camera?
Theoretically, just about any camera could work - it doesn't even have to be digital. However, the end product will be a video made from digital images. So if you use film, the images will have to be converted to digital files. That can be done by any good film processing service. But the real issue with film is handling and processing the large number of frames that you'd need to shoot. Even a short time-lapse movie typically requires hundreds of frames. With film, that gets very cumbersome and expensive; so I doubt that many photography enthusiasts would really want to approach this kind of work with a film camera.
Ideally, what you want is a digital camera that offers fully manual controls plus a few other helpful features that I'll describe a bit later.
Planning a Sequence
Careful planning is extremely important in order to obtain the desired results.
1. Decide what to shoot. Common time-lapse subjects have included clouds, celestial bodies, plant growth, vehicle movements, and industrial activity; but there are many other possibilities. My first time-lapse sequence was of saltwater on a plate evaporating and forming crystals.
2. Decide how long your shooting sequence should be, how long your final movie should run, and the frame rate that your movie will use. These decisions are interdependent, and are also related to the subject you choose. If you want a movie of a flower opening, it probably makes no sense to shoot a session that covers only 10 minutes of time - or one covering 72 hours of time. The first choice wouldn't show much change at all, and the second choice would almost certainly be overkill. You have to make a reasonable prediction of how much time your subject needs to show the degree of change that you'd like to see.
For example, let's say that you want to shoot cloud motion. Clouds can show considerable change over 40 minutes, so let's make that the length of the shooting session. Now, let's say that you want your cloud movie to run for 16 seconds, which is a reasonable length of time for a viewer to watch such a thing. The frame rate is always a fairly easy decision: make it 30 frames per second. This is a convenient standard for computer-generated video, and also allows you a little flexibility if you need to do something different later.
So... since your 16 second movie will show 30 frames per second, you'll need to have 480 frames to work with (16x30=480). And since you're going to shoot those 480 frames during a 40 minute (or 2400 second) period, you know that you'll have to shoot a frame every 5 seconds (2400/480=5). You also know that the action in the final movie will be depicted at 150 times normal speed. Easy, right?
3. Set up the camera and determine all of the exposure parameters. Here's where you'll want that tripod, or some other means of steady support. You generally must try to avoid any risk of the camera jiggling or shifting even the slightest bit during the shooting session (unless that's an effect you actually want to play with - more on that later). This is also the point at which you choose the lighting for the scene, the composition, the lens aperture and focus, and the shutter speed.
In most situations these settings will remain in effect for the whole shooting session, so think carefully about that. For example, your movie might not look so good if the camera changes the exposure parameters as the sun pops in and out through moving clouds. For such reasons, it's best by far to use a camera that offers manual shutter speeds, manual aperture control, and manual focusing.
Shooting a Sequence: The Intervalometer
Now you're all set. The subject is ready, the camera is ready, the lighting is perfect, and you have your plan. All you need to do is stand by the camera and press the shutter button every 5 seconds for 40 minutes. Well, you could. But what if your next project is shooting crystals forming in a plate of evaporating saltwater, every 3 minutes over a period of 48 hours? There must be a better way to do that... and there is.
An intervalometer is a handy gadget that automatically and repeatedly fires the camera's shutter according to a schedule that you specify. Some advanced cameras include a built-in intervalometer function, which can be really nice. But even if that feature is there, it might not be properly suited to the task at hand. For example, the Konica Minolta 7D has a built-in intervalometer. But there are two big problems with it: you can only program a maximum number of 240 frames, and a minimum interval of 30 seconds between frames. This would be okay for some types of time-lapse work, but useless for the cloud movie that we're making. Even worse, the 5D has no intervalometer feature at all (and neither do the Sony A100 and A700).
The solution for me was an external intervalometer that controls the camera through a cable connected to its remote control jack. It can fire an unlimited number of shots, at any interval from one second to 100 hours, in one second increments - perfect for time-lapse work.
The product is apparently manufactured by a Chinese company called Aputure and the only way I know of to get one is through eBay (search for 'Minolta remote timer' or 'Aputure remote timer'). Variations for several types of cameras are available for as little $50 shipped. Interestingly, it looks and operates almost exactly like the official Canon TC-80N3.
You're almost ready, but it's good to give some thought to a few potential issues before you push that intervalometer button and walk away.
1. What image resolution are you using for these shots? Your final movie is unlikely to require resolution higher than 720x480 pixels, which is standard DVD resolution; so you would be wasting a lot of pixels and memory space if the camera is creating 3000x2000 pixel files. Consider setting the camera to its lowest image resolution; and make sure that you have enough available memory to hold the number of frames that you intend to shoot.
2. How is the camera battery? You don't want it to run out of juice before the end of the sequence. And not all digital cameras can complete 480 shots with one battery - even a fully charged one. You might have to consider using an AC adapter, or a beefier power pack, or maybe even switching out the battery at some point in the sequence.
3. The camera's LCD is a battery eater as well. If it's set to display each shot taken, you'll exhaust the battery much more quickly. Turn the LCD off if you need to conserve power.
4. Is the lighting for your scene going to remain as you want it to throughout the sequence? For the cloud movie, the answer is probably yes. But for other projects that might span several hours or more, the answer could be different. You might have to provide artificial light in a controlled environment. Your camera has an internal flash, but using it will place another heavy drain on the battery. Photographic lights or an external flash (again with fully charged batteries or an AC adapter) might be needed. And make sure that the camera's white balance is set appropriately for the light source.
5. Finally, you'll want to take a few test shots and run a short test sequence to confirm that everything is working as expected.
A Moving Experience
Okay! So you've now made all the right choices and avoided various pitfalls. Press the intervalometer button and take a break. Then come back 40 minutes later and review the shots. You can probably play them in a fairly fast sequence right on the camera's LCD. Looks cool! Now you need to copy the files to your computer and fire up some software that can turn the sequence into a video. There are undoubtedly many choices here, but the program I use is AnimatorDV Simple+ and is available as a free download (look in the 'enthusiasts' section of the site).
This program appears to have capabilities far beyond my needs and experience, and I had a little trouble figuring out how to work it at first. Also be aware that it sucks up a large percentage of available CPU power, even when it's not doing anything. A few hints on getting started if you do choose to try it:
1. If you're prompted to configure a new project, specify Capture Settings of Full DV resolution at 30 frames per second. Once you see the main menu, select Sequences > Import Sequence. Locate your files and select one of them. The program will automatically import all compatible files (BMP, JPG, TGA, and TIF) found in the same folder, so you'll want to maintain special project folders that contain only your sequence files.
2. In the small Project window on the right, right-click on the sequence name and select Unlock from the pop-up menu. Right-click on the name again and select Activate/Deactivate. If you see a warning message regarding picture size, just click OK. You should then see the last frame of the sequence appear in the preview window. If it looks dim and you want to see it as it really is, drag the STORED/LIVE slider directly below the image all the way to the left. If you want to see other frames in the sequence, drag the large slider below that to the appropriate position.
3. Back at the main menu, select Sequences > Make AVI... and enter the following in the window that appears: Width: 720, Height: 480, and FPS: 30. In the upper right corner of that window, click on Select File and provide a destination filename and location.
4. In the lower left corner of the same window, click on Save AVI. In the Compressor list shown in the next window, click the down arrow and select the Microsoft MPEG-4 Video Codec if it's there. This one has been working well for me. If not, select any available codec for starters - but be aware that the Uncompressed option will produce an enormous file. The video building process should begin when you click OK, and a progress bar should be displayed. When it finishes, you can click the Play button in the remaining window to watch your movie.
Once you get the process down, I'm sure you'll want to go back and experiment with a variety of other options.
Great! What Now?
Now that you have a movie in AVI format, you can do what you want with it. Import it into Windows Movie Maker and jazz it up with further editing; add some music and burn it to DVD (if you have DVD creation software); upload it to your website; or email it to George Lucas for consideration. If you're like me, you'll probably want to figure out ways to improve on it, and start planning the next project.
Here are the first three sequences I made using the tools and techniques in this article. They're simple steps toward learning a new skill:
Evaporating Saltwater (1.3MB)
Cloud Motion with Rectilinear Lens (2MB)
Cloud Motion with Fisheye Lens (5MB)
An Unexpected Discovery and a Workaround
I did discover something during these projects that I wasn't really looking for, and didn't like finding. When I finished the saltwater sequence I noticed an obvious flickering effect in the video. The frames weren't uniformly exposed, even though I had the camera and flash unit operating in manual mode. I guessed that the flash (which was set at 1/16 power, as I recall) was not producing exactly the same light output with each burst. But this theory was blown when I saw the very same effect in the first cloud sequence. No flash was used there, and the sunlight was obviously constant during the sequence. The only variables left were the shutter speed and lens aperture.
The third video, which is a bit underexposed but fortunately shows no flickering, gave me the answer. The fisheye lens that I used in that sequence has a manually set diaphragm, and it's impossible for the aperture to change even slightly during a series of exposures. The lenses I used for the other sequences (Konica Minolta 50mm f/2.8 D Macro and 18-70mm f/3.5-5.6 D) are auto-aperture lenses. Even when used in manual mode, these lenses close down only for the length of the exposure, then re-open and await a command from the camera to close again. Obviously, there is some margin of error in the camera/lens system that closes the diaphragms. The variation has presumably been there all along, but it is so slight (maybe 1/4 stop) that I never noticed it in any still images. It becomes readily apparent with a series of images shown in quick succession. This is unfortunate, because the flickering really detracts from the viewing experience. Holding down the camera's depth-of-field button while shooting doesn't solve the problem.
Happily, there is a workaround: when attaching a lens, stop turning it just before it 'clicks' into place. The camera will think no lens is attached. Only manual focusing will be possible, but that's not a problem. The aperture can still be adjusted within a limited range, depending on how far the lens is turned - and it will stay put for every shot.
More things to try in future projects:
Instead of mounting the camera on a stationary tripod, use an astronomical telescope tripod with an equatorial drive. This will allow smooth panning and/or tilting of the camera during the sequence.
Forget the tripod and just walk around with the camera for 20 minutes shooting what I see every few seconds. This could make a wild video!
Set up the camera to point through my car's windshield and make a movie of my drive to work (at a perceived rate of about 3000 miles per hour).
Another possibility is stop-motion animation, where certain things - like Gumby, for example - are intentionally moved around in a scene between frames.
What are your ideas?
Text and images © 2007-2011 Ray Lemieux