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How to find the Centre of Gravity


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#1 Omar Sawalha

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Posted 16 October 2014 - 07:57 AM

Hi, 

 

I am a beginner and just acquired the Steadicam Zepher, im using a  fs700 camera stripped down however i have a weight plate to compensate the weight for the arm. 

 

I know that i need to balance the camera on an edge and find the balance point but was curious as to how this is done with a weight plate since my weight plate goes right underneath the camera and how i center the dove plate on afterwards?

 

 

Regards

Omar


Edited by Omar Sawalha, 16 October 2014 - 07:58 AM.

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#2 Victor Lazaro

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Posted 16 October 2014 - 09:14 AM

Hi Omar, 

 

Balance the camera and weight plate the same way you would balance a heavier camera. Take a short 15mm rod and place it on a table. put the camera on it and find the spot where the camera tips to the other side mark the postition of this axis with a piece of tape on the side of the plate.. Then turn the rod 90degrees and do the same thing in the other axis. the cossing point of these two axes is the center of gravity (CG) of the camera. Place your dovetail under the weight plate and center it with the CG.

 

Hope this helps.

 

Here are some good resources that you should get and read/watch/go to (if you haven't already)

The Steadicam Operator's Handbook http://www.tiffen.co...dicam_book.html

The Steadicam EFP Training Video http://www.steadicam...am_efp_dvd.html

Have you taken a workshop? This is the kind of information that you would get from it, along with correcting your errors and posture so you don't hurt yourself while making more stable images. http://tiffen.com/steadicamworkshops/


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#3 Omar Sawalha

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Posted 05 November 2014 - 09:50 AM

Hi Victor, 

 

Sorry for the late response i figured it out right after i posted the thread. I took a workshop a while ago and know all this information. However i had a little bit of a brain malfunction :$. But thank you very much for the tips.

 

Kind Regards

Omar


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#4 Dale A. Dimmick

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Posted 02 January 2015 - 03:55 PM

Greeting everyone. I need some advice. As background, I bought my first Steadicam from CP in 1979. A Universal II model. ser.#165. This was so early, that when I called Garrett Brown to ask for operating tips, he told me to meet him onset that night and he'd go over the basics with me. (Altered States) What a great guy.

 

So, this year a young friend I'm mentoring brought me a Chinese Steadicam asking me to check it out. I haven't operated for 15 years but I told him the key is balancing the unit correctly.  

 

My question is this: I'm mounting a large DSLR & Small DP monitor to the dovetail mounting plate. I spent 2 hours trying to balance the unit. I got it close, but even when it's balanced it still wants to float / roll and the bottom lags on starts and swings out at stops. The spin tests shows an oscillation as well. I tried less weight on the bottom, heavier rear weight to offset the DSLR - monitor weight on the dovetail...  The drop test is 1second. Lateral/vertical balance is good, until i rotate the unit.

 

It's been so long since I balanced a Steadicam, I must be leaving something out of the process. Please give me a few pointers as the you tube balance tutorials I've watched are incomplete.

 

Thanks in advance!


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#5 Joel San Juan SOC

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Posted 02 January 2015 - 04:13 PM

 

try this if you haven't already

 

J


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#6 Andrew Fewsmith

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Posted 03 January 2015 - 04:17 AM

Dale, if the "Chinese steadicam" is a liang, or similar knockoff It may never balance due to poor gimbal construction. I've never seen this before, but I have read similar stories to yours online where others have commented on the gimble bearings being faulty.
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#7 Michael Desiderio

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Posted 03 January 2015 - 04:41 AM

Greeting everyone. I need some advice. As background, I bought my first Steadicam from CP in 1979. A Universal II model. ser.#165. This was so early, that when I called Garrett Brown to ask for operating tips, he told me to meet him onset that night and he'd go over the basics with me. (Altered States) What a great guy.

 

So, this year a young friend I'm mentoring brought me a Chinese Steadicam asking me to check it out. I haven't operated for 15 years but I told him the key is balancing the unit correctly.  

 

My question is this: I'm mounting a large DSLR & Small DP monitor to the dovetail mounting plate. I spent 2 hours trying to balance the unit. I got it close, but even when it's balanced it still wants to float / roll and the bottom lags on starts and swings out at stops. The spin tests shows an oscillation as well. I tried less weight on the bottom, heavier rear weight to offset the DSLR - monitor weight on the dovetail...  The drop test is 1second. Lateral/vertical balance is good, until i rotate the unit.

 

It's been so long since I balanced a Steadicam, I must be leaving something out of the process. Please give me a few pointers as the you tube balance tutorials I've watched are incomplete.

 

Thanks in advance!

 

Pretty sure it's a crummy gimbal.  You could properly balance a post with bungeed rocks if you had a precision gimbal to support it.


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#8 Victor Lazaro

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Posted 03 January 2015 - 03:11 PM

Check the gimbal. Set the balance with the camera looking on the left as normal, then still on the docking pin, turn the camera to look on the right. Is the camera still balanced? If not, then your gimbal is out of alignment. Not sure how to fix it on a "chinese" stabilizer.


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#9 Frank Born

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Posted 03 January 2015 - 03:20 PM

I tried one of these, the gimbal post bearing may be off-center. There is a procedure to re-center it - if there are screws at the small bearings of the gimbal fork with this particular model. The other possibility: The bearing seats are not horizontal. Then you can't do a thing. (Sorry about maybe not getting all words right).
Cheers, Frank
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