2012-07-23T16:30:13Z

Balancing the Rhino Steady Camera Stabilizer, Case Study: Medium Size DSLR

Posted by Miguel Grinberg under Filmmaking.

This is the second article in my series about the Rhino Steady, a camera stabilizer made by Rhino Camera Gear.

In the first article I described in detail how this and other similar stabilizers work. In this and future articles I will describe how I balance different types of cameras.

Before we start, I think a couple of disclaimers are in order. I'm not associated in any way with Rhino Camera Gear, I just purchased their stabilizer during their Kickstarter campaign. I'm not an expert in stabilizers, I'm just writing about my own experiences with this one unit I own and the knowledge I acquired online. Do not take what I say as gospel, this is just my own experience, YMMV.

Today I will be balancing a DSLR, in this case a Canon 60D with a Sigma 17-50mm lens. The weight of this camera and lens is about 3.2lb.

So let's get started. Since I don't know any better, I always begin with this configuration:

  • The camera in the third (middle) channel in the stage, roughly balanced left to right.
  • The bottom weight holder with its cap in the first slot, without any weights and all the way out.
  • The front weight holder with its cap, without any weights and all the way out.

With this setup the first thing to check is that the top is heavier than the bottom, because I will be adding weights until I achieve balance. If the bottom is already heavier than the top then I would need to remove bottom weight and to do that I will need to resort to some tricks (which I will cover in a future article).

To test that the top is heavier than the bottom I just do the drop test:

Drop Test Drop Test

So this is exactly what I want, the camera is the heaviest part of the system.

I will now try to achieve a rough static balance by adding bottom weights. Here is how my static balance changes as I add more weight to the bottom. With one thin weight added the camera is still too heavy:

Balance Test

With two thin weights the camera is still heavy:

Balance Test

With three thin weights the bottom is heavy, note how the system goes the other way to find balance:

Balance Test

The fact that just by adding a thin weight to the bottom makes things change so drastically isn't a good sign. If I decide to settle on two thin bottom weights then I would have to figure out where to add additional weight to achieve static balance. And if I go with three thin weights the system balances way past the vertical point, so it's not useful.

At this point I know that unless I make a significant change I will not be able to achieve balance. The best configuration at this point is the one with three thin weights, so I just look at how I can improve its static balance, and by looking at how it balances I see two possible things to do:

  • move the camera back in the stage.
  • move the bottom weights forward to the next slot.

Given the fact that it is easier to move the camera than to move the weights I prefer to try moving the camera first and see if that makes it better.

So I move the camera one channel back and retest. As I mentioned before, each time the camera is moved the left to right balance is lost and needs to be redone. This isn't that hard, luckily.

So let's see how things look with the camera in its new position. Here is how it balances with two thin weights:

Balance Test

Here is with three:

Balance Test

And here is with four:

Balance Test

These look surprisingly good, we are definitely getting closer. I measured the drop time for each of the above configurations, and they are as follows:

  • with two thin weights: about 2.5 seconds
  • with three thin weights: about 1.5 seconds
  • with four thin weights: less than 1 second

From the above numbers I can discard the four weight configuration right away, since it is too bottom heavy. It's a pity, because it's the one that has the best static balance, but I would never be able to get the drop time where I want it, so now I know it has to be three or less thin weights in the bottom.

While the drop times with two and three thin weights are very decent, the static balance is not exactly how I want it, so I resort to a trick I have up my sleeve. If I screw the bottom weights in they will make the bottom slightly less heavy with respect to the top. In other words, the center of gravity would be moving up a bit. This will affect my static balance (I'll have to check if it makes it better or worse) and it will slow down my drop time.

Let's try this with the two thin weights. Here is how the static balance looks after I screw the weights in a bit:

Balance Test

This looks pretty good! But the drop time with this configuration is now in the order of five to six seconds, which is too long. While you may be able to get decent shots with the system balanced like this, due to the small imbalances that always exist the camera may drift away from the upright position, and then it will take it longer to find its balance again, or it may stay crooked for the rest of the shot.

So let's save this as a possible option to explore, but let's see if going with three thin bottom weights works better.

Now that I know that the static balance in this configuration improves when the bottom weights are screwed in, I can just screw them in the exact amount that gives me a perfect static balance. Here is how it looks with three thin bottom weights screwed in to achieve balance:

Balance Test

And the drop time in this configuration is a beautiful two seconds, so we are really really close now.

But there is one more thing to check. We still haven't done anything with the front part of the device, where you can also attach weights.

What I do to determine if the front is balanced is an alternative drop test. Instead of holding the stabilizer with the front up as I have done above, I now hold it horizontal and flat, with the front looking forward. Like this:

Balance Test

Then when I drop it, I look at how the front and the back of the stabilizer's body drop. Here is how it looks with my current configuration:

Balance Test

I'm not sure if the picture clearly shows this, but while the stabilizer is dropping down the front of the unit points a tiny bit up. That means that the front is lighter than the back. If you go out and shoot with the system in this state you may get minor unwanted rotations left or right, so it's better to address this.

And turns out this isn't terribly difficult to address, since I can just add weight to the front. Here is the drop test with one front thin weight added:

Balance Test

Obviously one thin weight in the front is too much weight, and now the system drops with the front looking down.

To fine tune it I screw the front weights in until I get the front to look forward while it drops:

Balance Test

As I mentioned in the introductory article, every time a change is made the balance need to be checked again. This isn't as bad as it sounds though, because as I'm refining the balance the changes I need to make are smaller, so they are less likely to cause a big impact in the remaining variables. I'm not going to post pictures of this step, but here are the results:

  • static balance: the unit now balances with the camera tilted down a bit.
  • dynamic balance: drop time remains at about two seconds.

To correct the static balance I just screw the bottom weights in some more, until the balance is achieved again.

After this last correction, I retest dynamic balance and it remains in the two second range, so I'm still looking good there. The alternative drop test looks good too, the front is facing exactly forward all the time during the drop.

I can now say that I have the system balanced to the best of my ability. If you know how to improve it even more, please let me know!

When you reach this point you want to write down the configuration you ended up going with, so that the next time you have to balance the camera you don't have to repeat all the steps. Here is how I take my notes:

  • Camera: Canon 60D + Sigma 17-50mm lens.
  • Weight: 3.2lb
  • Channel#: 2 (#1 at the back, #5 at the front)
  • Bottom weight arm thread#: 1 (#1 at the back, #3 at the front)
  • Bottom weights: 3 thin (19mm in)
  • Front weights: 1 thin (8mm in)

Note that for the weight packs I even write down their up/down position relative to the frame. My measure is for how much of the screw protrudes on the inside of the stabilizer's body, measured from the base of the plastic weight cap.

I hope this tutorial was useful. In the next article in the series I will show the steps to balance a lighter DSLR.

Thank you for reading. Please let me know what you think in the comments!

Miguel

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2 comments

  • #1 Anugrah Bahl said 2015-02-18T18:06:47Z

    I went through your procedure for Canon 60D (without strap) and 35mm 2.0 USM lens. I have much roll effect. how to do get rid of it. I started with 2nd channel from back and 3 thin weights at the bottom full stretched out. can you help? I am trying to shoot a video of the problem so I can explain clearly.

  • #2 Miguel Grinberg said 2015-02-20T06:28:18Z

    @Anugrah: you need to do the drop tests and ensure the system remains stable. I think a very minor roll problem is normal, I get it too if I move the camera fast.

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