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Running/Pendulum Motion


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#1 Jordan Tetewsky

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Posted 02 June 2013 - 04:17 PM

Hey guys. Operating a glidecam hd-2000 handheld without a vest system. One thing that's always bothered me is the pendulum motion I get when running- I was told increasing the drop time should decrease the pendulum motion, but that did not work. Here's a reference from a shot I took.

 

 


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#2 Alan Rencher

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Posted 02 June 2013 - 07:42 PM

It's the opposite: less drop time means less pendulum effect. It's caused by increased inertia. You can also eliminate the effect with increased control of the post when starting and stopping.

Edited by Alan Rencher, 02 June 2013 - 07:45 PM.

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#3 Mark Schlicher

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Posted 02 June 2013 - 07:43 PM

First, that's some pretty good results for running with a handheld Glidecam. On stairs no less.

 

Longer drop time does help with pendular motion, but it's a matter of controlling with your gimbal hand...it's not automatic. You must use your fingers and thumb to anticipate and counter pendular and other forces, to achieve clean lockoffs and keep your horizons level.

 

The Steadicam Operator's Handbook goes into the topic pretty deeply and I believe the EFP training video handles the topic, too. If you are serious about the craft you should get these both and study them thoroughly.

 

Also, one of the (many) limitations of the Glidecam, if I remember correctly, is that there is not a proper large-diameter grip under the gimbal. This makes it harder to control, including damping pendular motion.


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#4 Eric Fletcher S.O.C.

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Posted 02 June 2013 - 08:27 PM

It's the opposite: less drop time means less pendulum effect. It's caused by increased inertia. You can also eliminate the effect with increased control of the post when starting and stopping.

Actually incorrect.

 

you want the rig closer to neutral. The pendular effect is caused by the heavier end of the rig trying to stay put when the gimbal accelerates, if the rig is neutral (IE Zero Drop) the top and bottom of the rig weigh the same so when you push it with the gimbal everything moves together. 


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#5 Jordan Tetewsky

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Posted 02 June 2013 - 08:43 PM

First, that's some pretty good results for running with a handheld Glidecam. On stairs no less.

 

Longer drop time does help with pendular motion, but it's a matter of controlling with your gimbal hand...it's not automatic. You must use your fingers and thumb to anticipate and counter pendular and other forces, to achieve clean lockoffs and keep your horizons level.

 

The Steadicam Operator's Handbook goes into the topic pretty deeply and I believe the EFP training video handles the topic, too. If you are serious about the craft you should get these both and study them thoroughly.

 

Also, one of the (many) limitations of the Glidecam, if I remember correctly, is that there is not a proper large-diameter grip under the gimbal. This makes it harder to control, including damping pendular motion.

 

Alright sweet. I've never used a "real" steadicam, but it is something I've been considering, as I'm asked to do glidecam work a lot, and I'm doing so for a feature film in a month. My only concern is that I want to eventually be either a dp or director, and I don't know if steadicam operating is really the perfect place to start if I want to work my way up to that.

 

As for the large-diameter grip, is that just the soft foam padding underneath the gimbal? I'm sure I could add that on if that would help with eliminating pendular motion. 

 

Also, thank you for the replies.


Edited by Jordan Tetewsky, 02 June 2013 - 08:43 PM.

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#6 Mark Schlicher

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Posted 02 June 2013 - 09:48 PM

Jordan,

 

It is the grip directly beneath the gimbal, but it is not soft foam. It is textured hard metal. Some operators put bicycle grip tape or the like on it, but in order to be responsive it can't be squishy-soft.

 

The Glidecam post is both small and slippery. If you are very clever and have access to some machine-shop tools you could fashion an add-on grip. Practically speaking, the best you may be able to do is experiment with tape to increase the friction so you can improve control.

 

There are some brief explanations of grip, technique and related topics in the various Steadicam manuals that Tiffen has on the Steadicam website. Start with the Pilot and Scout manuals.

 

By the way, when I say "serious about the craft" I mean "serious about improving your work". It's not about your gear (except to the extent that your gear will limit you as you get better) or your ultimate career path. It's about caring about doing your best right now with what you have right now.

 

And you should invest in the Steadicam Operators Manual at your earliest opportunity. As a future DP or director (if you go that direction), you will get a real leg up on understanding how to collaborate with Steadicam operators more effectively.


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#7 Alan Rencher

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Posted 02 June 2013 - 11:22 PM

Eric, I meant to say that. I was thinking in reverse for some reason.
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#8 Nelson Reis

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Posted 23 June 2013 - 12:14 PM

Flying the zephyr for 3 days now ...im getting the same pendulum effect ...the sock and vibration of walking and running are gone but the pendulum Effect is there ... Im achiving a good result balancing the camera going by the instructions of the efp training ... what i thing im doing wrong is the drop time im going for 3 secs but i just realized my rig is way ligthter then that big camera ...the total of my rig is about 10 lb ...what drop time should i use for this pay load ?
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#9 Jerry Holway

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Posted 23 June 2013 - 12:40 PM

Same drop time for a standard length of rig. Really short rigs (like a Merlin) have very short drop times, superpost rigs have much longer drop times for the same basic effect.

 

Drop time is a compromise between the pendulum effect and having the rig seek some balance/attitude to help you frame or keep the rig vertical. Different operators like it more neutral (less pendulum, less help from balancing); other like it more bottom heavy (more pendulum effect to correct but more vertical/framing feedback). Some of the choice seems to be what's in fashion, but there are plenty of great operators working almost neutral, and others with 2 second or less drop times at a standard length. 3 seconds is just a good place to start, but experimenting with slower and faster drop times will teach you how to operate faster.

 

Regardless, one of the basic skills of operating is keeping the stick upright, preventing the pendular effect as one moves about.

That takes some understanding and some skill (practice). No quick way around it.

 

Jerry


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#10 Nelson Reis

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Posted 23 June 2013 - 07:21 PM

Thanks Jerry ... Just finished one more day of training and its getting better..will definally experience with different drop times ...i notice what i tend NOT to anticipate the move and will work on the next set of fligths ... Practice makes perfect especially flying ..")
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#11 Nelson Reis

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Posted 24 June 2013 - 11:39 AM

I had to re-watch the efp training video to check what i maybe doing wrong ...and i found my mistake ... I was holding the center post wrong i was trying to operate it rigth in the middle and not at the very top where the finger wraps around the bottom of the gimball giving way more control to the unit vs holding it in the middle ... This must be a common mistake that newbies without a workshop do ... Really enjoying learning this craft..;)
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#12 Jordan Tetewsky

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Posted 17 September 2013 - 09:34 AM

I thought I'd just ask. I used a much heavier camera than usual the other night (in total it was a 5 pound camera + the glidecam with two weights on each end all supported on my arm), and I found that panning fast was almost impossible, maybe because dynamic balance could not be adjusted- maybe in the first shot, the pendulum is do to poor dynamic balance? We ended up shooting it so that he hugged the wall when going up the stairs, to take the pan slower. Here's the shot I took; I did not choose the framing on the stairs- the director wanted the focus on the ass/bag, which was really hard for me to get. I don't plan to use this shot on a reel or anything, but feel free to add criticism.

 

Edit: There was also no wireless focus etc..


Edited by Jordan Tetewsky, 17 September 2013 - 09:40 AM.

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#13 Eric Fletcher S.O.C.

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Posted 17 September 2013 - 10:18 AM

NOTHING in that shot requires dynamic balance. The pendulare motion is caused by The rig being too bottom heavy, and your technique needs to be improved.

This is also a great example of why doing it all on STEADICAM doesn't work. Just sayin
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#14 Mark Baluk

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Posted 17 September 2013 - 12:31 PM

As for panning quickly, it was probably a combination of you not being used to the weight and the small diameter of the post on the Glidecam. A post with a larger diameter would allow you to have a better grip (and less effort).

 

With a heavier camera, it's going to have a big difference when you try to pan compared to a bare dslr which you could whip pan with the strength of a feather. That, and depending on how good the gimble is, I presume that could make quite the difference.


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#15 EH Marshall

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Posted 18 September 2013 - 02:09 AM

The main question here is: what do we get from watching the butt of a pizza guy walking up a set of stairs and then watching a bad lock off of a guy eating food? 


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