Slow Zoom for 3 Hours - Any Ideas?

[Jack Nitz]

I've had a request to do a slow zoom for 3 hours on a 12:1. A micro force won't be slow enough. I'd like to program a start point, end point, and then enter a duration. The only thing that pops up when I do research on this would be a remote head for timelapse that comes with its own proprietary FIZ motor and controller. If that's the only option, I may pursue that.

Wondering if anyone has done anything similar? Seems like Preston would have a way to do it or Arri but as far as I can tell they don't.

Thanks! 

[Aapo Lettinen]

Not sure if a mechanical device can keep it stable and constant enough. Both the lens mechanics and the motor device may become an issue.

But one could for example adapt a normal manual follow focus to accept the axle of a small hobby mechanics motor which had tons of reduction gears. Then use some off the shelf hobby pwm control board to tune the speed slow enough. Can then add extra reduction gears if needed to get it even slower but still constantly running.

Some electronics hobby shop which has robotics kits supplies will have those parts available. 

You would need to manually start and stop it unless wanting to program an Arduino or Pico etc to do that

[Aapo Lettinen]

Some small dc motor which has wormgear reduction stage and then additional gear for further reduction. Maybe 10 000 : 1 more or less? Then the motor running constantly at slow speed and the output axle turning the follow focus gear

[David Lawson]

This sort of thing is common in astrophotography.

Look for something that can control a stepper motor (steps can be so small as to be unnoticeable), and see if you can use that. OnStep is used for mount control, and may be useful itself or offer leads to something that is.

[Steve Switaj]

Well this might be a case of "when you have a box of nails everything looks like a nail", but I've spent most of my career doing motion control and this is the sea I swim in.

In fact, since I've been working in stop-motion the last few years, a 3 hour shot seems downright zippy.

Do you have AC power?

My absolute first go-to would be a small animation controller with some motion control capability. I would suggest something like the DragonFrame Animation software, which is a steal at $300, and is also a damn good framegrabber for timelapse because it can cycle through a variety of exposures so you can bracket if you're shooting something where the light changes.

 https://www.dragonframe.com/

A system like Dragon also allows you to draw a curve for your zoom, so you can tweak out the non-linearities in your zoom pull.

Dragon is (mostly) a software product but they offer a variety of low-cost motion control options, including a sketch you can use with an Ardunio to drive a step motor. If you're a little handy with wires, but it's actually really straightforward.

Google "DragonFrame for timelapse" It really is kind of a game changer conmpared with how we used to do it.

Is this a one-off, or are you doing some more involved time-lapse project? I might be able to set you up with someone in LA that could help you out with this stuff

Edited November 7, 2025 by Steve Switaj

[Steve Switaj]

Hammers.

 "when you have a box of hammers everything looks like a nail"

Long day.

[Albion Hockney]

I think you are in the motion control space—I don't think standard fiz motors could move that slow without a separate controller of some sort. 

I wonder if the FIZ on something like a BOLT or similar system can do this—not sure how they work. I'd ask a motion control company about it though.