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Wheights for pilot & Xh-A1


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#1 Bart Wierzbicki

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Posted 18 March 2009 - 10:37 AM

Hey,
Is there someone who has a Pilot with an XH-A1 ?
How much, which wheights and where do you put them ? :rolleyes:

I've read throught posts that people were talking of having a total wheight of about 8 Pounds.
But I haven't read that ...
It's not in the manual so where can I read more about that ?
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#2 John Brook

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Posted 18 March 2009 - 12:08 PM

Let me handle this question pros. For I have heard this response numerous times.

Bart I am going to give you the same advice that people feel the need to give all the newbies on this board over and over.

"Use the search feature and search the archives."

Wasn't that helpful?
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#3 Dave Gish

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Posted 18 March 2009 - 12:38 PM

Hey,
Is there someone who has a Pilot with an XH-A1 ?
How much, which wheights and where do you put them ? :rolleyes:

I've read throught posts that people were talking of having a total wheight of about 8 Pounds.
But I haven't read that ...
It's not in the manual so where can I read more about that ?


You want 8 pounds on top, and 2 pounds on the bottom (with the battery).

You'll need extra middle weights:
http://www.bhphotovi...nce_Weight.html

Each middle weight is 1/4 pound.
For the XH-A1 and the Pilot with IDX batteries, I would go with 2 middle weights on each side of the bottom. You'll probably want a QR plate on top, so add that to the top weight calculation.

Edited by Dave Gish, 18 March 2009 - 12:39 PM.

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#4 Bart Wierzbicki

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Posted 18 March 2009 - 04:00 PM

Let me handle this question pros. For I have heard this response numerous times.
Bart I am going to give you the same advice that people feel the need to give all the newbies on this board over and over.
"Use the search feature and search the archives."
Wasn't that helpful?


Oh yes ... thanks for the helpful information pro ... not !
I have used the search function and I already saw posts about the 8 pounds, but I was looking to see if it
is something which is officially stated by Tiffen or of it is just something that is proposed by users out of their
own experience.
The other question about the XH-A1 was just to ask if there is someone with a Pilot and an XH-A1 to find out what
is the best setup to achieve SB & DB. I didn't found it in the search or the archives and if I looked over it, my apologies
for that. Otherwise my big thanks to Dave Gish for his always helpful answer and explanations.
Hopefully some day I can also, like him, help other newbies as I am now to give them advice in their way of making the best out of it by trial, error, questions, searches in archives to make it as a steadicam-pro.

Edited by Bart Wierzbicki, 18 March 2009 - 04:01 PM.

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#5 Charles Papert

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Posted 16 April 2009 - 01:38 AM

Bart:

I hope your last month with the Pilot and A1 have been enjoyable.

It is critical to gaining an understanding of how to balance dynamically that one experiments with weights and masses in different places on the rig. While it's not the worst idea to cobble someone's "cookbook" settings, once you start adding accessories or changing cameras or even reconfiguring the rig for different applications, you need to be able to quickly and efficiently re-balance the rig dynamically. In fact, even extending the center post changes dynamic balance. It can be a slow and frustrating thing to learn and even for us "pros" it can be a tad difficult sometimes, but just like everything with Steadicam, the more you do it, the better you get at it.
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#6 Sam Morgan Moore

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Posted 16 April 2009 - 02:16 AM

Bart:

I hope your last month with the Pilot and A1 have been enjoyable.

It is critical to gaining an understanding of how to balance dynamically that one experiments with weights and masses in different places on the rig. While it's not the worst idea to cobble someone's "cookbook" settings, once you start adding accessories or changing cameras or even reconfiguring the rig for different applications, you need to be able to quickly and efficiently re-balance the rig dynamically. In fact, even extending the center post changes dynamic balance. It can be a slow and frustrating thing to learn and even for us "pros" it can be a tad difficult sometimes, but just like everything with Steadicam, the more you do it, the better you get at it.


Charles

I am learning flying Ex1

On the DB thing I think a lot of newbs like me are somewhat mislead by the concept of balancing using the adjustment on the top stage

I am developing this procedure

-Mark the camera CofG with tape or pen (by balancing it on a pencil off the rig)

-possibly make further marks on the camera for CofG with accesories/different batteries

Know that because the sled batteries sit low/close and the monitor high/far that the camera CofG must be slightly behind the post centre line for DB

-mount the camera with that mark maybe 5mm (or so) behind the post centre line (using the top stage adjustment to place it there)

-use the top stage to gain a horizon

- balance in the fore aft axis the rig by moving the battery and leaving the top stage alone - the camera has to stay at that 5mm (or so) position

Experiment with changing that 5mm with post length (longer = less ?)

S

Edited by Sam Morgan Moore, 16 April 2009 - 02:25 AM.

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#7 Charles Papert

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Posted 16 April 2009 - 12:25 PM

Sam: we all have different methods of going about it. I myself will spin the rig, determine which way it is precessing (falling) during the spin and then adjust both the battery and the top stage to reduce this to the point where it spins flat. Every time you move the battery, the rig will fall out of static balance so it stands to reason that you have to adjust the camera platform to fix this.
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#8 Eric Fletcher S.O.C.

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Posted 16 April 2009 - 01:02 PM

Sam: we all have different methods of going about it. I myself will spin the rig, determine which way it is precessing (falling) during the spin and then adjust both the battery and the top stage to reduce this to the point where it spins flat. Every time you move the battery, the rig will fall out of static balance so it stands to reason that you have to adjust the camera platform to fix this.



Actually in a perfect world we would mount the camera on it's CG and then move the batteries and Monitor in unison to achieve dynamic balance
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#9 Sam Morgan Moore

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Posted 16 April 2009 - 03:38 PM

Sam: we all have different methods of going about it. I myself will spin the rig, determine which way it is precessing (falling) during the spin and then adjust both the battery and the top stage to reduce this to the point where it spins flat. Every time you move the battery, the rig will fall out of static balance so it stands to reason that you have to adjust the camera platform to fix this.


What I am thinking - and I think I saw a similar post by one of the masters

it that one is trying to cut down the variables while hunting for DB - ie reduce the amount of combinations that balance statically but might/might not gain DB

that if the battery is lower than the monitor and heavier -we know that the CofG of the camera must be behind the gimbal for DB, in the case of a light rig like the pilot this distance from the gimbal is fairly minimal

by marking the camera and putting it in a reasonable position to start with the variables are reduced in the hunt

once one has found a DB for a specific post length (and I typically extend my post by the length of the allen key handle maybe 7cm) one can mesure the gimbal to camera distance (or eyeball it)

At that point to set up (from a broken down form) one gets post lenght and camera distance set and just fiddles with the battery until SB is acheived magically gaining DB at the same time - reduced variables

In summary would one agree that for newbs it is correct to think that..

-placing the camera CG a short distance behind the gimbal will lead to good start point for finding DB or an approximation thereof that is good enough for basic operation

-marking the camera speeds up this process

Of course the more experienced operator will need different rig configurations and a greater degree of DB to operate more demanding shots

S

Edited by Sam Morgan Moore, 16 April 2009 - 03:48 PM.

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#10 Sam Morgan Moore

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Posted 16 April 2009 - 03:44 PM

Actually in a perfect world we would mount the camera on it's CG and then move the batteries and Monitor in unison to achieve dynamic balance


Sorry I dont understand that - maybe being thick/newb !

If the monitor is lighter than the batteries and at a different height and/or distance from the post surely there is no DB to be gained with the CofG of the camera over the gimbal

I hope the OP does not consider this to be threadjack..

SMM
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#11 Charles Papert

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Posted 16 April 2009 - 04:15 PM

No, this is correct in terms of the theory of DB I subscribe to. In the case of an inverted T-shaped rig where the monitor and battery are equal counterweights, the CG of the camera should be over the post. Once the monitor rises, the battery comes forward and the camera moves back. The classic image to illustrate this is the monitor raised until it is at the same height as the camera; the camera obviously has to be pushed backwards to share a CG with the monitor, and the battery will now be centered under the post, making an upright T. Or, see page 34 of Jerry and Laurie's book!!
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#12 Alec Jarnagin SOC

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Posted 16 April 2009 - 04:21 PM

OK, here goes a few thoughts and I'm sure I'm over simplifying things, but I hope this helps...

The camera's CG frequently does end up behind the post because on many rigs (most notably the Tiffen rigs) the monitor is raised far above the battery base, meaning that they are truly separate masses (if you raised the monitor all the way to the camera platform, it would now be part of that mass and you'd obtain DB by sliding your batteries forward to be under the center post while moving the camera/monitor mass backwards). Conversely, if you lowered the monitor and placed it right in line with the batteries much like the XCS sled (and to a lesser degree, the PRO) then you slide the batteries back. In short, on an XCS rig, I think you'll find that the camera's CG is almost directly over the post whereas on an Ultra, the camera's CG will be slightly behind the post. Neither is better; just different.

I look at it slightly differently. Rather than thinking about placing the camera's CG behind the post, I leave my sled slightly front heavy. Thus, I can be reasonably quick & sloppy when I throw a plate on the camera and more often than not, I skip the rolling the camera on a tube to find the CG. I'd add that I can usually do this because I regularly see the same model cameras and experience tells me plate placement. From here, I then slide the camera on the top stage until static balance is achieved. This means the camera's CG is now slightly behind the post because I had left my sled slightly front heavy. From here I tweak, but I have found this is a damn good starting point. I should add that I keep my post short and usually leave it that way but if this is changed I do need to factor it in.

For monitor to battery placement, take a look at these rigs:

Attached Files


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#13 Alec Jarnagin SOC

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Posted 16 April 2009 - 04:23 PM

While typing, Charles beat me to it with (as usual) a simpler and better explanation....
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#14 Sam Morgan Moore

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Posted 16 April 2009 - 04:25 PM

No, this is correct in terms of the theory of DB I subscribe to. In the case of an inverted T-shaped rig where the monitor and battery are equal counterweights, the CG of the camera should be over the post. Once the monitor rises, the battery comes forward and the camera moves back. The classic image to illustrate this is the monitor raised until it is at the same height as the camera; the camera obviously has to be pushed backwards to share a CG with the monitor, and the battery will now be centered under the post, making an upright T. Or, see page 34 of Jerry and Laurie's book!!


But in the case of the Steadicam Pilot where (rigged 'normally)

-the monitor sits above the sled

-the battery hangs below it

- the battery is heavier than the monitor

- the monitor is positioned near the end of the sled ie away from the post

the camera would need to sit behind the post
for DB to be possible

Correct?

Thanks for the time BTW (and yes I have the read the primer many times)

S
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#15 Charles Papert

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Posted 16 April 2009 - 04:38 PM

That should work Sam. BTW it is probably best with the Pilot to slide the whole lower spar rather than move the battery in and out when making adjustments. Bottom line is this--start with the setup you describe, then check how the rig spins. If it tips to the nose, move the lower spar back and slide the camera forward. If it tips back, do the reverse. Don't worry about where the camera CG is located at this point, just adjust the components until you have a clean spin.

And to clarify once again--extending the post will change the relationships of the masses, which affects DB. Raising or lowering the gimbal does NOT change DB however.
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