How To Turn Your iPhone Into a Stop Motion Camera

By Will Smith

If you have a smartphone, you're a tripod, an inexpensive app, and a few hours away from shooting your own stop-motion videos.

Shooting short time-lapse movies is time consuming, but the barrier to entry has never been lower. You're probably an inexpensive app and a $30 tripod away from having everything you need to get started.

I have a pretty well established love of Lego, so it's no surprise that I might want to do a time-lapse video of a lego build. I've seen several great ones on YouTube, as well as great stuff posted by Crimson Jester and Fink in the forums. My goal was to do something a bit more complex than a simple time-lapse--I wanted to make a video where the model seemed to assemble itself--time lapse wouldn't cut it for that. Instead, I needed to learn about stop motion filmmaking.

The tools I used for this are simple, but overkill for a project of this size--a Joby Gorillapod Focus with the Ballhead adapter with a Glif iPhone 4/4S tripod adapter. If you're buying a tripod specifically for this, it's much cheaper to use a dedicated iPhone tripod mount, but I already had these on hand. I used the Frameographer app to shoot the video. Frameographer includes the tools you need to make a great stop motion video at 720p. There are some more specialized apps for stop-motion, so before you start a massive, multi-hour project, make sure you do your homework to make sure Frameographer is right for you. It doesn't allow you to export individual frames, edit frame order, or make any adjustments after your set is broken down. Finally, I needed a subject. In this case, it was the midi-scale Imperial Star Destroyer I bought at Bricks by the Bay a few weeks ago.

What's the difference between stop-motion and time-lapse? In time-lapse, you simply set the camera to shoot a frame at a fixed interval--the interval can range from a few shots a second to a few shots per day. The goal with a time-lapse film is typically to compress the passage of time. On the other hand, with stop-motion films, you manually control each time the shutter opens, painstakingly positioning your subjects, aligning them, and making sure that every frame is perfect. The downside is that this can take a long time; such a long time that there's a South Park episode about it. You typically record video at 24fps, which means you'll get about 1 second of video every 24 times you open the shutter, and it will take 1440 exposures to get a full minute of footage. I love stop motion because it lets you imbue life in objects that are normally inanimate.

Before you start shooting, you need to secure your set and choose your subject. Because I chose to do a stop-motion Lego assembly, I didn't have to write a script or build models to shoot, but that would fall under the general rubric of "preparation" as well.

You should also take a moment to consider lighting. While it's tempting to use natural light for your shoot, it's usually a better idea to use artificial lighting for stop-motion animation. The length of time it takes to set up each shot will make it difficult to maintain a consistent exposure throughout your shooting day. The good news is that your phone's camera probably handles low-light shooting reasonably well, so you shouldn't need to use much more than your room's existing lighting.

It's also a good idea to prep your phone. I ran a power cable to the phone and set it to never automatically lock, which meant all I had to do to take a shot was tap the shutter button, without having to wake up the phone each time. I recommend turning vibrating notifications off or switch to airplane mode--you'll want to do everything you can to avoid moving the camera once you start shooting.

When you're ready to start shooting, make sure your shot is framed properly, with enough room for whatever you're actually going to shoot. Take some test shots in both your starting configuration and the finished config, before you shoot your first frame. You don't want to spend a few hours on the opening, only to realize your shot positioning will need to change at the 60% mark.

It's a good idea to shoot a few opening frames with no movement--I didn't do this, and really wish I had. It lets the viewer get used to your starting position. You'll also want to enable onion skin mode. To do that in Frameographer, tap the second icon from the left in the top row in the capture window. Onion skin mode overlays the live view from the camera over the previous frame, making it much easier to control your characters' movement and avoid having accidental movements in your film. There really isn't a trick to onion-skin mode--you just need to find a couple of points of reference on any object that moves and make sure they align properly from frame to frame.

As a general rule, you should shoot several mostly static frames on either side of transitions with lots of movement. This helps the viewer adjust to changes in context. When something major happens, as when I attached the bridge to the Star Destroyer, it would have been smart to shoot a transition from one position to the other, and maybe even devote a second or two of the final movie to showing off the major addition. It's also wise to go back and watch every few dozen frames, to make sure your positioning hasn't drifted. A pixel or two of accidental movement each frame can make your finished movie look really janky.

If you want to get started with stop-motion animation, Lego makes a great subject. Doing a stop-motion build is a relatively easy way to get started--it took me a mere six hours to assemble and shoot a 423 piece kit. The studs on top of each Lego brick are a great point of reference to ensure you only move what you want to during your build. When you're ready to go farther, playsets and mini-figs make great sets for your short films, at least until you're ready to build models and sets from scratch.

I did learn a few specific things shooting a Lego build. First, the overhead 2/3rds angle that Lego uses in its instruction manuals works great for a time-lapse build. It lets you see enough detail to be interesting, without requiring a tricky overhead camera setup. The less you can move the model when placing a brick, the better off you are. Realigning your model after you've moved it takes a lot of time and is frustrating.

Attaching bricks takes a fair amount of force, both when you push the brick onto the model and from the hand holding the model in place. Unfortunately, I found that applying enough pressure to keep the model from wiggling when you place a brick causes the model to wiggle when you release the hand that holds it in place. This is a bad thing. To fix this, I use a three-step brick placing technique. First, I apply a fair amount of pressure to the model with my left hand, locking it in place. Then, I place the brick with my right hand. Finally, I apply gentle pressure to the model with my right hand while lifting my left hand from the model. The gentle pressure from the right hand is usually enough to stop the wiggle that plagued my early efforts.

That's really all there is to it. Be sure to post your time lapses in the forums when you've finished them. I'm going to take another stab at stop-motion later this month using a real still camera and Final Cut Pro X.