Using a Jib arm with a digital still camera is something new to most still camera users.
You will likely have better luck with posting your question on the Camcorders Forum.
http://forums.cnet.com/camcorders-forum/
Here is a short video of a Jib arm being assembled.
http://www.youtube.com/watch?v=kO7oomLHuuU
It does show you how you select the correct counter-weight.
Just a matter of offsetting the weight of the camera.
Think of it as a balance scale when selecting the amount of weight.
I assume you are using a very sturdy tripod.
A light weight tripod will flex too much when you add the weight of the camera plus counter-weight plus the weight of the Jib.
If any of the members of this forum have any experience with using a Jib,
now is a good time to jump in with both feet.
I suggest you visit a camera store (not a department store).
Many large camera stores will rent a jib to customers.
A short rental will probably come with some good advice from the camera store.
..
i have a 4' ProAm DVC50 jib and a velbon PH 368 tripod head. i use this set up with a canon rebel T2I camera. i use 7 kilograms of counterweights. now i'm not this experienced with this type of equipment so i am having a bit difficulty getting smooth movements. are there any tutorials were i can learn a bit more or does anny one have some advice on how to get smoother moves?

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