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Old October 19th, 2002, 02:13 AM   #1
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I too have questions for Charles Papert

Hi there. Seeing as how you are the god of the steaicam, I had some queries for you. My buddy's going to help me put together one of the designs from homebuiltstabilizers.com (no, not the real fancy ones, the one that says "$14 steadicam." I was wondering if you could help me with some things.

I know that a big part of being a successful operator is the operator him/herself, and not the rig. Could you carefully describe the magic walk that you use?

Also, I've noticed all the pro rigs have the monitor on the bottom. I have an LCD monitor, and thought about trying to make a little shoe similar to the one on the XL1s's top that attaches to the bottom of our rig, so I could have a monitor on the bottom too. I was wondering what the logic behind the placement was, though.
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Old October 19th, 2002, 03:13 AM   #2
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To have a stab in the dark Josh, I don't think the idea behind the placement is a technicial one. I think it it's just so you can see the monitor and also where you are putting your feet. With a steadicam and a camera swinging through the breeze the last thing you need it to come a cropper and end up on your butt surrounded by a few dollers worth of camera parts.
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Old October 21st, 2002, 10:12 AM   #3
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I think experience and trial and error are the words here. Try
try try till you don't want to lift the steadicam anymore and then
try some more :) .... but, perhaps Charles has some more words
of wisdom and advice. Good luck.
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Old October 22nd, 2002, 01:12 AM   #4
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(thunder sound FX)

Quake and tremble ye mortals! For the god of Steadicam speaks at last!

(lightning, more thunder)




OK, enough of that. Me no god Josh, just another weary journeyman camera operator.

But to answer your question--the better the stabilizer, the less important your actual "magic walk" is. There is something of a gait specific to Steadicam that is a bit hard to describe here, but it is nothing like the knees-bent duck walk that a good hand-held shooter adopts. The reason for this is that a good Steadicam-type system will isolate the camera from the shocks generated by a standard walk (even a flat-out run).

However, a cheaper system and certainly a $14 homebuilt will not be able to provide as sophisticated an isolation, and thus you will have to augment with a handheld type walk. It's sort of a gliding shuffle, where you bend your knees and roll your feet from ball to toe to avoid a definitive footstep.

As far as the monitor, Adrian guessed correctly that it is positioned low on the rig so that you can see where your feet are going (a definite advantage over handheld operating). In addition, having it below the balance point means that it acts as partial counterweight to the camera, so you don't have to use as much dead weight at the bottom.

Good luck with your project, Josh.
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Old October 22nd, 2002, 05:00 AM   #5
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Well, let me ask about the dead weight. I weighed the XL1s a while ago, and it weighs around 6.5 pounds. We put 7 pounds on the bottom. I read elsewhere that the counterweight is supposed to exactly match the weight of the camera. What's the deal here?


By the way, do not have a project to use this device for. I just wanted to have one so I could play with it, and didn't want to spend $450 or so on a steady tracker.
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Old October 22nd, 2002, 07:53 AM   #6
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Counterweight equals load weight *only* if the fulcrum point is exactly midway between the two.
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Old October 22nd, 2002, 07:58 AM   #7
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Having never seen a Steadicam or a Glidecam in person, I have a stupid question... how do you control the focus and zoom? Is there a controller built-in? If not, can something like a Varizoom controller be attached?
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Old October 22nd, 2002, 10:13 AM   #8
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Chris is a law-abiding citizen and is thus showing his respect for the laws of physics. Don't mess with Mother Nature, right?

Josh, imagine holding the pole horizontally, with your hand in the middle with the camera at one end and an equal weight at the other. Now slide your hand toward the camera. The other side will want to drop, yes? If your hand ends up just under the camera, it stands to reason that a much lighter weight could be used at the other end to balance out. For your project (i.e. homebuilding project), perform the same experiment with a 2x6 plank the same length as the pole you intend to use balanced on a fulcrum (something narrow that lets it act like a see-saw), this will allow you to rest the camera and weights on top of the wood to figure out how much weight you need to achieve your goals.

John,

Usually the zoom function is replaced by the operator's legs, in that if you want a tighter shot you just walk in to it. Most of the time, that's a more desirable look than doing a zoom anyway. As far as focus, as we all know you barely have to touch the focus ring on a DV camera until you are zoomed in substantially, and Steadicam is most often used for wider-angle shots, so it's generally a set-and-forget type of operation. (although it can be beautiful at a telephoto range, at which the dreaded autofocus could be pressed into service at a pinch, if available on the given lens).

For a situation where it is still desirable to zoom, a Varizoom could be incorporated. Steadicam-type stabilizers don't like cables coming off the rig though, as they tend to interfere with the isolation. A suggestion for those who are flying stabilizers and discovering that they are fighting cables: Make sure to use the most flexible (droopy) cables you can find, and have them hang off the camera in a big loop, then you can either fasten them off via your support hand if you are using a handheld stabilizer, or off to your vest if you are using that type. What you want to avoid is a cable exerting its own forces on the system, and making a big loop tends to avoid this.
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Old October 22nd, 2002, 12:53 PM   #9
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Okay Chris, just to clarify, when I do my fulcrum test with the plank, I want the fulcrum to be where my hand would? or just right in the middle of the plank?
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Old October 22nd, 2002, 01:00 PM   #10
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Josh -- you want the fulcrum to be right where you grip it.
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Old October 22nd, 2002, 01:06 PM   #11
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Alright. I guess we went about the weight thing all wrong. I'll get plank and do the test. Thanks.
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Old October 23rd, 2002, 12:08 AM   #12
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Just to clarify something else about the placement of the hand:

With any expanded-mass stabilizer such as we are talking about (anything from a weighted pole a la the Steadytracker up to a full-fledged Steadicam), it is critical to establish balance in three axes. These are: fore and aft, side to side and top to bottom. Fore and aft and side to side are best adjusted at the camera mounting platform; the ability to slide the camera back and forth to find the optimal balance (so that the rig doesn't want to tilt up or down) is important. Likewise with side to side.

It is possible to add or reposition accessories to make adjustments in balance, but it's a bit finicky. One example would be if the system lists to the side, try sliding the viewfinder left and right on its track to help balance to a level position.

If nothing else, you can adjust your bottom weights to help find level. Ideally, your weights are positioned dead center under the pole and the camera's center of gravity is over the pole. This is called dynamic balance, and the unit will function best in this situation.

The third axis, top to bottom, is adjusted by where your hand grips the pole in a handheld rig (or in the position of the gimbal where applicable). However, that pivot point should NOT be at the center of gravity of the system as measured from top to bottom. In other words, if you placed the fully loaded rig onto that famous fulcrum in a horizontal fashion, mark the spot at which the pole balances. Then center your grip an inch or two ABOVE this point. The reason for this is that a very slightly bottom heavy rig will tend to stay more level.

The higher you grip, the more stable the rig. The tradeoff is that it then becomes very hard to tilt up or down; requires more force. Also, coming to a sudden stop will cause the rig to tip out in a pendular fashion.

The happy compromise is to grip just above the center of gravity. With a gimballed setup, set the gimbal at this point and the guide hand will fall on the center of gravity.

Somewhat arcane stuff, and I'll be happy to clarify if needed, but it's pretty critical to understand this to achieve the best results.
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Old October 23rd, 2002, 04:18 AM   #13
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my fathers name is Charles.
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Old October 23rd, 2002, 05:08 AM   #14
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We went about this the ghetto way (no offense to those living in ghettos). The screw on the top of the pole goes into my Sachtler tripod plate, which screws into the camera. There can be no slidage, the way I see it.

To counteract the side to side sway, there is a handle that sticks out on one side halfway down the pole, to be gripped with the non-pole hand.

The weights are indeed dead center at the bottom of the pole.

I was going to do Chris's test, and figure out where my hand is comfortable, then get a plank of the same length as the pole, mark the equivalent on the plank of where my hand would be on the pole, then put a fulcrum under that point on the plank, and add weight as necessary until a balance is achieved.
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Old October 23rd, 2002, 06:03 AM   #15
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Josh,

Take a look at this bogen adapter

http://www.bogenphoto.com/

search for a model 3273 Universal Sliding Plate

Jeff
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