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Old April 3rd, 2010, 05:25 AM   #1
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balancing 12" jib advice

Hi there

I have bought a 12" jib and unfortunately havent had a chance to set it up yet.

What Im wondering is what are the basic principles of using the weights to balance it.

Do I need to just get it to a level horizontal position or do I adjust the weight depending on what kind of shot I want to acheive? ie if Im wanting a from high to low swoop, I use less weight so the camera end wants to drop etc

any advice or tips appreciated!

Thanks

Jamie
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Old April 3rd, 2010, 12:13 PM   #2
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Do you mean 12 foot? -12"- means 12 inches in many English speaking countries (particular in the USA where we have this eternal inability to convert to metric for whatever reason...).

With any jib, the idea is to get the camera onto the jib with everything you need on it...in order to actually balance, you'll need the camera and head of course, the battery, shooting monitor, matte box, etc, etc on board. Those of us who have different size batteries need to have the ability to change the balance appropriately.

Most people place the camera end of the jib on an apple box or something that supports the weight, then they add the weights in the field. Ideally most people like the balance to be such that the camera doesn't rise by itself, or sink by itself...it floats. This way the operator isn't fighting the pull of the jib. on the other hand, sometimes countering a slight pull up can help to give videographer something to brace themselves against a bit...

Like most things, there is a huge allowance for personal preference here...
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Old April 3rd, 2010, 12:16 PM   #3
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As Tim says, it should be weighted so that it just floats, allowing a finger tip push to rise or lower it. Take not of the maximum weight limit of your jib - you don't want anything to snap!
I have a Hague Multi Jib, and one of its best features is a small sliding weight on the arm to allow fine tuning - otherwise the weights that you have may be slightly too heavy or too light - this fine tuning allows you to get it just right.
Steve
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Old April 3rd, 2010, 12:46 PM   #4
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Quote:
Originally Posted by Steve Phillipps View Post
I have a Hague Multi Jib, and one of its best features is a small sliding weight on the arm to allow fine tuning - otherwise the weights that you have may be slightly too heavy or too light - this fine tuning allows you to get it just right.
Steve
Boy, do i agree on the sliding weight... One of the best features you can have on a jib.

If you don't have this, I would think you could devise one with some sort of a generally available clamp...

In the old days, I used to use a strap with some big washers...slide it back and forth. Crude and unsophisticated...

(It fit my personality... :-) )
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Old April 3rd, 2010, 06:51 PM   #5
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Quote:
Originally Posted by Tim Kolb View Post
Do you mean 12 foot? -12"- means 12 inches in many English speaking countries (particular in the USA where we have this eternal inability to convert to metric for whatever reason...)...
Yes a 12 foot jib. A 12 inch one would be a little limited!

Ok..make it float. I will have a go at that. I also like the idea of adding some heavy washers on a belt and clamp to fine tune it.

Thanks for the advice!

Jamie
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Old April 3rd, 2010, 07:39 PM   #6
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Hi Jamie............

Something to make note of.

Never leave the jib unattended outdoors if the camera end has not been secured with some sort of tether.

With the jib balanced, it only takes the slightest breeze to get it swinging at a quite astonishing velocity and if there's anything to hit, it will.

Likewise, keep a wary eye on your ceiling height if working indoors. A 12 foot jib, an 8 foot ceiling and 10 kilo counterbalance weights make for a bad combination, especially with 5 grands worth of camera on the business end.


CS
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Old April 3rd, 2010, 09:55 PM   #7
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If your jib doesn't have a sliding weight system built in a simple and inexpensive way to achieve it is to get some ankle weights that have velcro straps. Then you can make fine adjustments.

Another thing that gives me a little more peace of mind is to tether your camera to the end of the jib. That way if some weird fluke thing happens and say the head falls off your camera won't come crashing down to the ground.

I also usually have an extra couple of ankle weights at my landing point (apple crate or bundled up blanket) to place on the end of the jib when it's not in use. No matter what though, I'd never leave the jib with the camera on it unattended.

Garrett
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Old April 3rd, 2010, 10:53 PM   #8
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There is also the uncontrollable third agency, the uninvited hand, usually attached to curiosity. "Mmmh, interesting. I wonder what this does?" - snap, click, thud - "Uh-oh! - OMG. - Oh thank you Lord. - Nobody saw it. - Better move on".

Also be mindful of hyperfocused people failing to watch where they are going and losing some scalp, blood and hair on something hovering at head height.
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Old April 18th, 2010, 07:47 PM   #9
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Quote:
Originally Posted by Jamie Roberts View Post

Yes a 12 foot jib. A 12 inch one would be a little limited!
Hi Jamie,

Don't write off small Jibs.
I have not tried a 12" jib but find my 24" one very useful for close-up natural history work - insects, flowers and the like. The ability to change height etc quickly is very useful particularly when the boom is well balanced.
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Old April 18th, 2010, 09:02 PM   #10
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Hi Alistair,

What jib do you use? I've been seeking a short jib and would be interested in your thoughts.

TimK
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Old April 19th, 2010, 01:36 AM   #11
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I hope that I am not hijacking the thread.

Hi Tim,
These comments probably won’t help much if you are looking for a custom solution. The only commercially available component was the Miller ball cup at the centre of it all. The rest is home made. In its original form it was used under water with a large 16 mm camera and it is made out of stainless steel, anodised aluminium and other sea-water resistant materials. The tubular sections of the legs are interchangeable with longer legs. The square section of the boom shown is longer than I thought at 31”. I also have a boom about 6’ long and another at 11’.

For underwater use the original boom was set in a suitable position and locked off, it had a fluid head on its extremity and the idea was to permit a variety of camera positions without shifting the tripod. The original tripod head is now in the conventional position and carries a moveable boom. The boom movements are damped. The method of attachment makes it possible to slide the boom forward or backwards and the upper linkage can be adjusted to suit. The camera can either be mounted above or below the end platform. The picture shows a fluid head in the underslung position and as this head is a side-mount the camera can be used very close to the ground.

It is very awkward to carry more than a step or two but is nice for close up work.
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Old April 21st, 2010, 09:03 AM   #12
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In addition to the comments above I should add that one of the advantages of using a damped boom is that if it not balanced it will rise or fall at a rate related to the degree of unbalance. Furthermore if an unbalancing weight is hung from the boom by a cord the movement stops when the weight reaches the ground. For a very gentle stop a metal chain can be used as the unbalancing weight, in this case the rate slows as the first link of the chain touches the ground and then slows further as successive links come to earth. Thus it is possible to simply vary the rate of rise or fall as well as where and how quickly it stops all without touching anything.
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Old April 21st, 2010, 09:59 AM   #13
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If you want to balance a jib over its range of movement what you need and what many don't have is a "vector bar". This is just a rod pointing up 90deg from the jib that carries a small weight. Its function is to counter the change in moment of the other counter weights as the jib is raised and lowered. This stops the jib 'running away'. The only jib I've seen use this is the Porta Jib Traveller from Losmandy and it is a good addition. Not that hard probably to add such a thing to any jib.
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