Yes, it will work (at least to some pretty good extent).

To understand what's going on, you have to look at the physics of the situation.

A hand held film camera is free to move in 6 dimensions (this is the 6 degrees of freedom you hear CG guys talking about).

3 of those dimensions are translations, or linear motion, 3 of them are rotations.

Ok in english...

• It can move up/down (Y translation)
• It can move left right (X translation)
• It can move in/out (Z translation)
• It can pan (rotation about Y)
• It can tilt (rotation about X)
• It can roll (rotation about Z)

When most of us hand hold a camera, it's doing all of these, to some extent.

Now, of the two kinds of motions, rotations are far more disturbing than translations.

If you're wandering up and down 3 inches as you walk the image is floating up and down 3 inches in the frame, not a lot of shift if you're photographing a room or a car.

But if you're also pitching the camera 3 degrees back and forth as you walk (tilting or rotationg about X), then the image can be moving vertically across a big chunk of the screen with every stride.

OK, we can solve this problem, we just have to make the camera less sensitive to the rotations of tilt and roll.

Now, here's where the law of physics come in.

We're all familiar with inertia, right. In a nutshell one of its effects is that heavy objects move more smoothly than light objects, because they have less suceptability to outside forces.

More smoothly is good.

There's a similar concept that can be applied to rotating objects. It's called Polar moment of inertia.

Resistance to turning.

Again, in a nutshell, an object that has its weight spread out has a higher PMI and is more resistant to turning than the same wieght in a compact form.

Try this, take 5 pound weights hold one in each hand.

Clasp them to your chest then try to turn around quickly.

Now hold them out at arms lenghth and repeat the experiment.

Both the business end of a Stedicam and your DIY stickcam use this principal.

They take the weight of the camera, and a secondary weight (batteries and monitor on the stedicam, weight plates for you) and put them on opposite ends of a 2 foot long stick.

Then they grab the stick near the center of gravity.

If you do this you'll see that the camera now has a LOT of resistance to tilting or rolling, because to get a little bit of tilt or roll, both the mass of the camera and the mass of the weight have to move a lot, in different directions, and neither one really wants to. (remember, objects at rest and all that...)

But note that you can still pan easily because the mass is still all near the pan axis.

Tricky, huh?

Now, with the disclaimer that I am not a Stedicam operator, some practical advice.

The last time I tried this, I used a commercial version of your stickcam. I don't recall what it was called.

I had a pole about 2 1/2 feet long, with a fairly heavy Arri SRII on the top end.

There was a 3 pound weight with an adjustable clamp down near the bottom, and an adjustable handgrip near the middle.

You find the handgrip position by turning the pole horizontally and finding the balance point.

Usually the counterweight is lighter than the camera, so the ballance point is closer up toward the camerat than it is to the weight. This is OK, since it puts the camera at a good height for a comfortable arm angle.

Stedicam operators have a little gimbal bearing that they clamp at this point.

It's pretty important that you hold it near the ballance point. you may be tempted to move your grip up the shaft, since this makes the weight a pendulum that tends to level the camera, but the unballanced weight will also pitch the camera down when you suddenly push forward or pitch up when you pull back.

Lastly, hold the grip lightly, so the pole can pivot freely and the ballancing weight can do its job.

- Steve

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