DIY: Build a Simple Wireless Follow Focus … with LEGOs?

By James DeRuvo (doddleNEWS)

If you have kids, chances are, they’ve got a boat load of Legos. And if their older kids, then chances are those Legos are just collecting dust in their toy box. The great thing about this toy is that it can be used to prototype or craft just about anything. Like perhaps, a DIY wireless follow focus for your DSLR? So why not put them to good use!

Wireless follow focuses are very helpful when you need to control and adjust your lenses when the camera is on a steady cam, crane, or gimbal. Granted, you need a second operator to do it, but they’re quite handy. Unfortunately, they’re also pretty pricey, ranging from $1,000-5,000 a piece. That’s a big hit to take for a one man crew, or a low budget indie filmmaker, but using your imagination, and a few Legos can get the job done. You just need to pick up a few extras.

This wireless follow focus technique comes from one of my favorite DIY Filmmaking Channels on YouTube, Indy Mogul. The latest host of Backyard FX, Jake Kassnoff, takes a bunch of Legos, and a pair of Lego Mindstorms EV3 computer controllers and cobbles them together to create one. The technique in the video above also uses Technic pieces, rubber toy tires, and some special gears to link everything up. This is where you will run into a bit of a hiccup though.

The gears aren’t designed to line up with a follow focus gear you attach to your camera lens. It requires 3D printing a gear that will transfer the motion from the LEGO gears to the Follow Focus gear. And that is something that Jake doesn’t share.  There are, however, several sources, including GrabCad and Thingiverse, where you can find one to download, augment, and 3d print.  To make changes, check out Tinkercad. It’s a great way to get your feet wet with 3d modeling. And if you don’t have a 3D printer, there’s always a local Maker Space (usually at a community college) or even a local Office Depot could offer the service.

On top of that, Mindstorms controllers aren’t exactly cheap. The standard ev3 starting kit is about $350 on Amazon. But if you’ve already invested in them for your kids, then you have them lying around. And there’s no denying they work. You can drop the price by going with an older model on eBay. However, going with an older model loses the wireless benefit. And even if you can pick up a used ev3 set, multiplying it by two and that’s still well on your way to buying a lower end WiFi follow focus unit that at least looks legit. But there is another DIY option … using an R/C controller and a few extra parts. Check out this build by FilmLook:

If you think about it, this is probably how wireless remotes were created in the first place. With a simple servo motor and an RC controller, you can move gears to adjust focus. The parts list is really easy to get on eBay or at a local R/C shop:

  • 1x Wireless RC Controller with receiver
  • 1x Servo Motor with screw
  • 1x 4AA Battery pack (With on/off switch)
  • 1x 0.8 pitch gear
  • 1x Hot shoe mount
  • 1x Rod mount

You have to join the servo motor to part of a 15mm clamp to attach to your standard rod, but I think using epoxy or hot glue would be a better option long term. But duct taping them together to get the design spec’d out doesn’t hurt. But as a professional, you’re going to want to close up the additional wires and connections to make it look cleaner. And the benefit of the wireless R/C controller is that you can place tape on it to indicate the range, and then mark that tape to dial in your focus points.

The real takeaway on this build, is the price … $80 and you have your own wireless follow focus. Not band for shooting with DSLRs. At the end of the day, it’s a much better way to practice with one, until you can afford the real deal. And it would be fun to build with your budding junior filmmaker!

About James DeRuvo 801 Articles
Editor in Chief at doddleNEWS. James has been a writer and editor at doddleNEWS for nearly a decade. As a producer/director/writer James won a Telly Award in 2005 for his Short Film "Searching for Inspiration. James is a recovering talk show producer from KABC in Los Angeles, and a weekly guest on the Digital Production Buzz with Larry Jordan.

Be the first to comment

Leave a Reply

Your email address will not be published.