Timelapse Photography using iMovie and Drift HD Ghost Camera

Thought I’d try my hand at producing a timelapse video, I’ve seen quite a few over the years and really like the city scenes, night sky and nature footage. But, before I go hard-core and setup my Sony SLT-A55 DSLR, tripod and automatic remote trigger, I wanted to do some experimentation and understand the full process involved from capturing the initial photos through to editing and creating the output video.

There is a good how-to guide on timelapse photography on the Digital Photography School website which I would recommend reading first to give you an overview an insight into this form of photo shooting.

Drift HD Ghost

As I usually commute to and back from work with the Drift HD Ghost camera mounted on the bike, I decided to use the cameras built in timelapse feature as the experiment. With a fully charged battery and empty SD card, I departed the northern suburb of Madeley at about 8am on 14th August and headed south to my place of work in Victoria Park.

The camera was setup using the following timelapse settings:

Sequence Interval: 1 second (1 picture every 1 second)
Resolution: 11 mega pixel per picture (image resolution: 3840 x 2880)
Image Format: JPEG
Image File Size: approx. 800kb per picture
Field of View: 170 degrees
Exposure: +/- 0EV

The journey duration was approximately 32 minutes in which the camera took 1920 photos. The images are stored in folders on the SD card, with a maximum of 999 images in each folder. So the images for this journey were placed in two folders.

Once I copied the folders onto my mac, I wanted to place all the images within one folder, so that importing and editing in iMovie becomes much easier to handle.

As mentioned the images are placed in folders, each folder contains a maximum of 999 images, and each images filename is sequenced numerically within the folder. So the first folder contained images named TL000001.jpg, TL000002.jpg through to TL000999.jpg, surprisingly however, in the second folder, I expected to see filenames TL001000.jpg, TL001001.jpg, etc.., however, the numbering sequence resets itself, and starts again with TL000001.jpg, TL000002.jpg, etc..

In order to merge the images into one folder and to keep the order of images in sequence I first needed to change the filenames of the images in the second folder to flow on from the last image in the first folder. So in the second folder I needed to change TL000001.jpg to TL001000.jpg, and do so for the next 921 images in that second folder. An extremely tedious, luckily though I have an app on my mac called A Better File Renamer which allows for bulk file renames in a matter of seconds.

I now have one folder with 1920 images named and sequenced correctly from TL000001.jpg through to TL001920.jpg.

iMovie

I used iMovie to compile my timelapse video with a playback rate of 20fps. However there are a couple of nuances in iMovie that you need to overcome in order to generate this type of movie.

Remove the Kens Burns (Pan and Zoom) effect applied to each image.
Display an image for 0.05 seconds in order to achieve a desired rate of 20fps.

Step 1 – Import images into your movie project

Create a new project with no themes, titles, transitions, etc.., just a plain vanilla movie project. In this empty project import (drag and drop) all the images within the Drift HD folder prepared earlier.

Step 2 – Remove Ken Burns effect

Select all the images in the timeline (CMD+A) and click on the Adjust option. Select the Style settings icon and either choose Fit or Crop to Fit. This will remove the Ken Burns effect from all the images and either fit the entire image into the scene, or crop the image to match the movie settings.

Step 3 – Change the duration of each image

By default, any image imported into an iMovie movie will have a duration of 4 seconds, meaning each image will be shown for 4 seconds before moving on. In order to achieve 20fps, I only want an image to show for 0.05 seconds (0.05 seconds x 20 images = 20 images per second = 20fps).

Unfortunately iMovie has a minimum allowable duration for images which is 0.1 seconds, which equates to 10fps – which for timelapse is a bit too jerky. However there is a workaround to get to the 20fps but it involves a few more steps.

Firstly re-select all the images in the timeline and click again on the Adjust option. From there select the Information icon. You’ll see that the duration is set to 4.0 seconds. Change this value to 0.1 (maximum allowed) and press Enter.

This has now set your image duration to 0.1 seconds per image

Step 4 – Export and import

Using the menu options File > Share > File, export the movie to your harddrive. Once processed you’ll have a bare-bones 10fps movie clip.

Create a new movie project within iMovie, again with no themes, titles, transitions, etc..

This time import the newly created clip into your new timeline.

Step 5 – Speed up the clip

Select the clip from the timeline and click on the Adjust option one more time. This time choose the Turtle icon which allows you to speed up or slow down the clip. From the Speed setting, choose Custom and enter the value 200, this will increase the speed of the movie by 200% from its base speed (currently 10fps) and effectively produce our desired frame rate of 20fps.

Again using the menu options File > Share > File, export the movie to your harddrive. Once processed you now have a bare-bones 20fps movie clip.

Step 6 – Finalise

You can now create a new themed movie, import the new second clip and add all the titles, soundtracks, and transitions you desire.

Results

I’ve posted my footage on YouTube which you can see here and I’m quite impressed with the output. I think I’ll still do some more experimenting with the Drift HD camera with different capture settings and frame rates before I go to task with the full DSLR gear.