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Time-lapse Tutorial
> About Time-lapse
> How Time-lapse Works
> How to Create Time-lapse Video
> Time-lapse Calculator
About Time-lapse
Time-lapse is like a fast forward for reality; it allows you to
observe things happening faster than they actually occur.
Time-lapse helps us understand the world by visually showing changes
that we cannot normally perceive. You could sit for several days
in the same place and watch a flower bloom. But the change happens
so slowly that you could not mentally compare one state of the flower
to the next.
The human visual system is designed to detect change. Our eyes and
minds can perceive complex changes in a scene better than any instrument
or computer system. But it functions only at a certain speed and
timescale. Time-lapse allows us to tune the speed of change
to the speed that our own eyes and mind can best understand and
appreciate.
How Time-lapse Works
We will use the term "movies" (things that move)
to refer to both film and video. Movie cameras actually record a
series of still images, called frames. From 18 to 60 frames
are recorded per second, depending on the movie format. These still
images are then played back at the same rate. The human eye perceives
this rapid series of images as actual motion.
Time-lapse movies are created by recording frames more slowly. The
frames are then played back at the normal rate.
Consider a movie in the cinema which is normally recorded at 24
frames per second. You could create a time-lapse by recording one
frame every second. When you play the movie, the frames recorded
over a period of 24 seconds are played back in one second. So the
recorded scene moves 24 times as fast as the real scene.
One hour of recording would play back in (60/24 = ) 2.5 minutes.
Some tips on creating Time-lapse Video
There are many considerations when creating a time-lapse movie.
Here we will present techniques using digital technology, and offer
a few practical tips.
Digital Techniques
- Video Camera Feature: Interval Record
Mode
Requirements: a video camera with "Interval" record mode.
Many video cameras, such as any recent Sony DV camera, include
an "Interval" record mode with which you can set the camera to
record a few frames of video at a specific interval, i.e. every
30 seconds, or every 10 minutes. This is a great feature for time-lapse,
but unfortunately does not yield very smooth results because it
always records a few frames at a time and the number of frames
recorded is not always consistent. To get a smooth time-lapse
the camera needs to record only one frame at a time. We can only
hope that camera developers will figure out the utility of this
feature and integrate it into future systems.
To record time-lapses using interval recording you need only to
activate it in the camera itself and then let it record. Easy!
One complexity that you encounter here, as with all techniques,
is the question of how often to record an image. See our free
online time-lapse calculator for help
with your calculations.
Example: On a Sony camera, recording a 24 hour day at 1 image
every 30 seconds takes up 8 to 10 minutes on a DV tape. This compresses
to about 30 - 60 seconds of finished video depending on how fast
the clouds were going and how interesting the day was.
- Speed Up Video
Requirements: a video camera or webcam, a computer with a large
hard drive, software to speed up video.
A great way to create smooth time-lapse videos is to simply record
a whole tape of normal video with a video camera. Then, transfer
the video to the computer, saving it to one file. The main limitation
with this technique is that you can only time-lapse an event that
fits on one videotape. (Usually 1 hour.)
This can be overcome by skipping the videotape and recording video
directly to the computer. In this case the length of the recording
is only limited by the size of your hard drive. (See our time-lapse
calculator for help.)
Once the video is saved to the computer hard-drive you can create
a time-lapse by speeding it up with software, and saving out a
new video file.
There are many software options:
- Expensive video software such as Adobe Premier, Adobe After
Effects, Sony Vegas Video, Apple Final Cut Pro, Apple Motion,
AVID programs and others offer excellent control over the
speed of movie files.
- Windows Moviemaker is included with the Windows operating
system and starting with version 2 you can apply an effect
called "Speed up, Double". By applying this effect multiple
times you have some control over how fast the clip plays.
- Record images
Requirements: a digital still camera or a webcam, a computer,
software to record images periodically, software to assemble images
into video.
This technique can be the most complex, but also allows you to
create the best quality time-lapses. You will need software that
can do interval recording. Many digital cameras come with some
basic software to do this. Or you can buy some software specifically
for this task.
Attach the camera to the computer, and use the interval recording
software to record a digital image periodically to the computer.
Once the images are recorded you need to assemble them into a
video file. This can be done with advanced software such as Adobe
Premier and the other software listed above. Or there are several
good software options.
- Movie
Salsa for Windows. $20.
- HandyAvi
for Windows. $40.
- GBtimelapse
for Canon Cameras and Windows. $50.
- IStopMotion
from Boinx for the Macintosh. $40 for standard version. $350
for high resolution version.
With a bit of web searching you can probably find some free tools
as well.
This technique offers the highest quality because of the superior
quality of the image sensors in digital still cameras. Also you
can create a very high resolution time-lapse video.
Practical Tips
Creating a time-lapse movie is a kind of experiment. When you record
normal video you can see the result in the viewfinder instantly, and
make adjustments right away to get exactly the shot that you want.
With time-lapse, you only see the result at the end, and since it
can take a long time - it is best to prepare your shot thoroughly.
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Change |
Think about what things around you are changing.
Sky, Street, Food, People. |
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Timescale |
Think about how long it takes for something
to change.
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External Factors |
Think about what other conditions might affect
your recording. Light, Wind, Weather, Pets. |
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One Change |
Best results are often when you can isolate
just one change, eliminating all other factors. For this reason
indoor recording is often best. |
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Tripod |
Usually you will want to record from a fixed
location. Use a tripod. A heavy tripod minimizes the possibility
of the camera being moved, even if accidentally bumped. Expect
to pay around $100-$200 for a good tripod. It is worth every
cent. A great supplement to a full-sized tripod is a JOBY.
These portable tripods are light, incredibly versatile and attach
to almost anything.
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UPS |
If you are recording a very long time-lapse,
consider investing in a Uninterruptible Power Supply (UPS).
Its a battery based system that ensures that your camera/computer
keeps running even if the outlet power goes out for a few minutes
or hours.
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Good lighting |
Recording indoors allows you to control the
lighting situation. |
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Do not disturb |
Consider who or what might interrupt the recording.
Because the recording is often running by itself it helps to
record in a closed room - and/or with a sign letting people
know what is going on. |
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Patience |
!!! |
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