Time lapse dolly
Lots of love to the LMR community from Finland!
Introduction: (Skip this if you dont have time to read general bullsh*t)
A time-lapse, for those of you have missed it, is basically a video/film that is speeded up a lot(the opposite of slow-motion). The actual/real time of things happening in a 10 second timelapse can be anything from minutes to hours to years. There are amazing time-lapses on the internetS, everything from fruits decomposing/rottening,flowers opening, grass growing, stars on the night sky and amazing nature scenes with clouds moving really fast etc.
Time-lapses has always fascinated me. It is somehow relaxing to watch although you would expect it to be really hyper-stressful when everything is moving faster than what they normally do. Since I bought my first DSLR camera a couple of years back I have tortured the cameras shutter by forcing it take a huge amount of pictures for timelapse sequences.
After seeing the amazing timelapses by Dustin Farrel (landscapes volume 1 and 2), Sean Stiegemeier,(Eyjafjallajökull, vulcano) Milapse (with his dynamic perception) among others, I realized that making the camera move during timelapses makes it even more cool and more beautiful. I decided that I wanted to build a timelapse dolly.
I have tried to build two different kind of setups before this one but I did not like either of them. They where both driven with a continuously rotating servos geared down with sprockets (No shoot-move-shoot capability (did not control the camera), not enough torque to lift the camera straight up) and where not robust enough/travel-friendly enough for my needs.
So I decided it is time to build a small, light, travel-friendly, more advanced setup.
There are not many commercial time lapse dollies out there, and the ones that are available on the market are unfortunately not in my price range, and if you buy one you miss half the fun. ;)
The building process
The Dolly, mechanical magic
After hours of googling around I found a interesting solution for making a simple, what seemed to bee quite stable, camera dolly that is firmly attached to the rails (allows you to let the camera travel straight up/upside down along the rail). The Dolly design i adopted is called the "Juiced link slider".
Although the Juiced link slider" is pretty cheap for a dolly, I recon I could manage to build one cheaper myself.
I decided to use a M20 (metric) coupling nut (95mm long) as the hexagonal base and 8 skateboard bearings as contact point to the rails.
After confirming that my idea will work on paper I started to build the hexagonal base by threading the holes in the coupling nut for a snug fit. On the second try after re-thinking my workflow, I got the tolerances fine enough for all the bearings to (almost) continuously touch the bars.
I added a cheap camera ball head for fast and easy camera attachment.
I wanted to be able to control the movement of the camera slider in such a way that taking long exposure time lapses and HDR (multiple exposures) timelapses where possible. To achieve this, it was essential to make the slider stop while taking the images, so the slider needed to move, then stop and shoot and then move again. Thus, the electronics needed to be able to control the camera. I decided to use a simple, easy to use/fast to program, yet effective microcontroller. A picaxe 28x1.
I planned the circuit schematics on eagle cad. The circuit consists of a voltage regulator, a dual channel optocoupler to allow for isolated camera control (focus and trigger), hybrid motor controller, and a place for a Eeprom.
I etched the PCB using "toner transfer" method.
It is always scary to hook up the circuit to 12V power-supply for the first time. Your heart is pumping and you are waiting to witness magic smoke leave the components. But it worked fine, no smoke on the outside! :) I built a enclosure to the electronics-motor unit and added a timing belt fastener to the trolley.
Then it was just a matter of programming to make it do what I wanted. I tried to keep it as simple as possible. By using the push buttons I am able to choose the essentials:
- Direction of travel
- How long it should travel between shots (motor speed and high time)
- Time of exposure, (how long time the optocoupler is high, allowing for taking HDR sequenses)
- Time between shots
Then the display informs me roughly how long time the camera buffer has to put the pictures on the memory card before next series of images.
Now the only thing that I will have to figure out next is to learn how to take and edit beautiful images.
Have a nice day!