153957 Photography

Basics

Definition

Time-lapse: Denoting the photographic technique of taking a sequence of frames at set intervals to record changes that take place slowly over time.
When the frames are shown at normal speed, or in quick succession, the action seems much faster.

So, what exactly does this mean and how do we achieve this 'Time-lapse' effect? You'll need a camera and a subject that changes over time, like a sunset or flowers. Then simply need to take photos at a different speed then at which you will play them back.

Example

Take a total of 100 photos, taking one photo every 10 seconds (100 photos x 10 seconds = 1000 seconds).
Make a movie playing at 25 fps from these photos, the movie will be 4 seconds long (100 photos / 25 photos per second = 4 seconds).
This movie will speed up time by a factor of 250 (1000 seconds / 4 seconds = 250).
So if a flower normaly takes 30 minutes to open, you can show that flower opening with a movie 8 seconds long.

Using this basic knowledge, you can take the photos at a shorter or longer interval and play them back faster or slower to achieve different effects, it is advised to choose the playback speed in such a way that the motion of the movie is smooth, not to fast nor to slow.
You can make a Time-lapse movie from just about anything, just let your imagination take control.

Requirements

The camera

For this you can use a digital or analog device. Digital would be best as that will make the following steps much easier.
The device can be a photocamera, videocamera, webcam or something equivalent.
A very important thing is that you can control the interval at which the device takes pictures, either on the camera (here is a list of camera's that can do this, see 5. Suitable Models) or via the computer. It also needs to have enough storage to be able to hold all the pictures that you want for your Time-lapse, this can also either be storage on the camera or a computer.

Stability - a tripod

A tripod is very useful when making a Time-lapse movie, it will ensure that all pictures are aligned correctly.
If you don't have a tripod use a flat and steady surface instead.

Trigger - a computer

If your camera doesn't support interval shooting on its own; use a computer to control the camera.
You will need to connect the camera to the computer via an USB cable. A laptop is more useful because it is more flexible, and can be taken to places where a desktop computer can not, but you do have to make sure that your laptops battery will last long enough.

Content - a subject

Of course you also need something to make the pictures of, preferably something that moves (not to fast), for example:
Clouds, flowers, ice, clockwork, people, animals, stars.
Try to predict how the subjet will move and make sure that your camera covers the correct area.

Taking the pictures

Some cameras, like mine, have a built-in intervalometer which allow you to take Time-lapse photos without a computer.
If your camera doesnt have this option (or if are using a webcam) you need a computer with the right software to take control over the camera.

Depending on your software/hardware/subject you must select an interval (e.g. 5 seconds) between each photo and the total amount (e.g. 500) of photos to be made. Then initiate the shooting and wait while your photos are being taken. Then tranfer them to your computer (if you where using the computer to make the photos, the photos most likely will already be on the computer). When this is done you can make a movie out of them.

Exposure mode

Usually you should put your camera in Manual mode (a fixed aperture and exposure time), because that will prevent a lot of flickering in the resulting movie. Make sure that you take some test shots before starting the time-lapse to make sure everything is set correctly. Sometimes, when lighting conditions are very inconsistent, it is wiser to let the camera to determine the exposure time (and hope that it chooses it wisely). You should then use Aperture priority mode (fixed aperture), use this to make the aperture smaller (=higher F number) to further reduce flickering, while letting the camera decide the appropriate shutter speed. If there is still flickering in the movie, see the Advanced section. You should NOT use Auto White balance, but rather set the camera to a specific white balance preset to keep that constant throughout the movie.

Manual focus

If your camera supports manual focus and your subject will remain at approximately the same distance; use manual focus. If you use auto focus your camera might fail to focus or accidently focus on the wrong thing. Using manual focus will also increase your camera's battery life.

Computer controlled

When using a computer to control your camera make sure that the camera's USB mode is correctly set. Most cameras can be set to either 'Mass Storage' or 'PTP', for controlling the camera via the computer choose PTP mode.

Power

If you intend to make a long Time-lapse or if you are shooting via the computer I suggest you use an AC-adapter for the camera: to keep it powered for an unlimited time. I almost always use an AC-adapter when shooting Time-lapse, it is more reliable then a battery.

Intervalometers

There is a lot of software and hardware available to control cameras for Time-lapse shooting, here are some examples:

Mac Software: Bear's Hand iStop Motion Camera Control Pro (Nikon dSLR)

Windows Software: Flix GBTimeLapse (Canon cameras) Camera Control Pro (Nikon dSLR)

Other intervalometers: The Time Machine Pclix LT100 Aputure Timer 'Virtual Finger' CHDK firmware (Canon cameras) Built-in intervalometer

Screenshots:

Canon S60 built-in Intervalometer

External Intervalometer

How to make movies out of pictures

Once you have made the photos for your Time-lapse movie you will want to make a movie out of them, here are some tips to help you do that.

Tip; First frame

If you have to press a button on your camera to start the time-lapse shooting I suggest you do this:
Often when you press the botton on your camera, to make the first photo, you move the camera a little bit, this causes the first photo to be a bit off center when compared to the photos, therefore I suggest you remove the first photo before you make the movie.

Software

There is a lot of software that can help you to make a movie from your images. Some are free, some are not, some are better then others, some offer more options then others... I suggest you take a look at all of them and see which fits best with your needs.

Software	Mac	Windows	Linux
PhotoLapse		x
Virtual Dub		x
Avidemux	x	x	x
Adobe Software	x	x
Apple Final Cut	x
Apple Quicktime	x	x

Making the movie

Here are two simple but effective methods to make the movies with Apple Quicktime, one with the Pro ($30) version and one with the free version. And also some basics for using Adobe After Effects. I have included some screenshots to help you find your way more easily. I will assume that all frames for your movie are in one folder and in correct ordered, by name (by index number).

QuickTime Pro ($30)

- You do not need to resize the images first for a smaller movie; you can resize the movie when you export it
- Open QuickTime Pro
- Go to File -> Open Image Sequence... -> choose one of the images
- Select your preferred Frame rate, you can experiment with different frame rates to see what works best for your movie
- Check/play the movie, make sure there are no bad frames (e.g. not aligned properly, over- or underexposed)
- If there are bad frames, you can remove them either by selecting them in quicktime and deleting them, or removing the files from the folder and rebuilding the movie
- Go to File -> Export (if you want to save the movie at lossless quality use File -> Save)
- Choose a codec, configure it to your specifications, choose a location to save it to, choose a name for the movie, and Export!
- If you want to be able to playback movies on an iPod/iPhone: Choose "Movie to iPod/iPhone" in the Export options

I use these export settings -> Export movie to MPEG-4, Video Format: H.264, Data rate: ±1024 kbits/sec, Image size: 640x480 VGA

Framerate :

File menu:

Export options:

Export dialog:

QuickTime (free)

- You may want to resize the images first for a smaller movie, because this can not be done when saving the movie, and playing a movie at very high resolution will probably not play smoothly
- Go to File -> Open File... -> choose the last image. this will open a new movie player with the image
- Now select all the other images (in the Finder/Windows Explorer), select them in correct order, then drag them on the just opened movie
- Each frame will be added in correct order (the order in which you selected them) and each frame will play for 1/15 seconds, so the movie will be 15 fps
- To save: try to close the movie window (either via the File menu or by pressing the close button), doing this will bring up the save dialog
(note: you can not save via the menu File -> Save, see screenshot)
- Choose "Safe as a self-contained movie" then choose a name for the movie and location to save to and press Save!
You're Done!
- This movie will be saved lossless, which means that the movie will be about the size of all the original images that are in the movie. If you intend to distribute it over the internet; compress it first.

File menu:

Close dialog:

Save dialog:

Adobe After Effects ($200+)

- Go to File -> Import -> File... (or use command+I on a Mac)
- Navigate to your image sequence, select all images of the sequence, check the checkbox to import the image as a sequence (see screenshots), then choose Open
- If the images are in RAW format you will be shown a RAW settings window where you can tweak you images to get the best results - A new movie will appear in the Project panel of After Effects, this is the movie you just imported
- Drag this movie either to the timeline at the bottom or into the Composition area
- Now you can add effects and other transformations to your movie, you can play around with that if you want
- There are several ways in which you can export this movie:
- I prefer to use: File -> Export -> MPEG-4 and use the same settings that I use to export from Quicktime (see above).
- Another way to export movies: Composition -> Make Movie, this will add the movie to the Render Queue where you can choose a bunch of settings and then export the movie.

Basic interface:

Import menu:

Import dialog:

Raw settings:

Composition:

Time stretch:

Export menu:

Render queue:

Advanced

Removing flicker

If you have made your Time-lapse movie and it turns out that the lighting conditions where such that your movie has a lot of flickering (brightness differences between consecutive frames) in it, you will probably want to have that fixed. But you dont want to go through every picture and try to equalize their exposure, that would be to much work. Luckily there is software out there that can help, for instance there is a deflick plugin (free) for VirtualDub (free). I have not used this software, because I have a Mac and this only works on Windows. There is more software that can help remove flicker, but not all are free, one of such is GBDeflicker ($80).