How to Use a Camera Dolly for Time Lapse Videos
We've discussed how camera motion can be used to add powerful dynamics to time lapse videos. In my last article, I went over the basics of using a motion slider to create precise, controlled camera movement along a plane. This time, let's look at a piece of gear that can help you create both linear and curved motion. A camera dolly is one of the most versatile ways to control camera movement in your presentations.
In the motion picture industry, camera dollies are enormous, bulky devices that may take more than one person to operate. Fortunately, for DSLR-based time lapse videography, the requirements aren't quite so strenuous. They can also be surprisingly affordable. Take a look at one of my favorite basic kits, for less than a hundred bucks from Revolve Camera.
Let's go over the basics of using a camera dolly in your time lapse sequences:
Choose your subject: This step may seem a bit obvious, until you consider that if you're adding camera motion, you can shoot a static subject as well as a moving one for your time lapse sequences. With a dolly, you can even move your camera around the subject! You can also cover much longer distances than you can with a slider. Find something interesting, whether it's moving or not.
Determine the motion path: Start by walking around or by your subject while looking through your viewfinder or in your LCD. Find the path and level that best highlights your subject and uses the surroundings to the best advantage. Spend some time playing with different ideas and find one that works well. If possible, you might want to draw a line to follow.
Set up the dolly: A simple dolly is something like a skateboard with wheels that can be realigned to alter the motion path. If your path doesn't curve, make sure your wheels are straight. To follow a curved path, set the wheel alignment and test the results until you find the correct angles.
When you're happy with the motion path, set up your camera mount and your motion device. The best dollies will allow for adding an elevation post for the camera mount and provide options for attaching something to push or pull the dolly easily. You may also want to mount supplemental lighting as well as an intervalometer if your camera doesn't have a built-in one.
Test the path and timing: This step will probably be the most complex, and it's one of the most important. How you proceed will depend on whether you plan to shoot a video of fixed length, a set number of exposures, or simply shoot until you reach the end point of your path. Another factor will be whether you move your dolly manually or with a motorized control.
Test and re-test your path until you're certain of the results. If the duration of your shoot will be short, do a “dry run” to test the timing. If you'll be shooting for a longer period, check your calculations and set your motor speed or movement steps accordingly. Take the time to get it right.
Shoot the sequence: Finally, the last step. Set up your dolly at the starting point. Start your shutter timer and, after the first exposure, start your motor or move your dolly to the next location. (This is where you're going to really appreciate that motor if you have one.) Once the sequence is complete, you're ready for the next subject!
Nothing to this camera dolly stuff, right? Seriously, the process takes practice and patience, but the results can be well worth the time and effort. Here's a short video that shows just a few examples of what you can achieve with the right camera dolly:
Check out the camera motion solutions at Revolve Camera. You'll be impressed with the simplicity, quality and reasonable prices of their dollies and other motion gear. Have fun shooting!