Newbie question about tripods

Chris Soucy · December 6th, 2008, 10:53 PM

Take 2:

Quotes 1 & 2:

Hmm, it's possible the LS38 camera plate is different to any other I've known and thus has a moveable VHS pin.

BTW, that's a spring loaded pin designed to engage in a matching hole in the camera to stop the camera rotating on the plate.

If that is the case and it can be moved, indeed, try to mount the plate as closely centered to the centre of gravity as possible, then lock it off and forget it.

All further adjustments with regard to camera centering on the head should be done with moving the mounting plate/ camera assembly forward or backward in the head slot.

Quote 3:

OK, the reason for counterbalance.

Unlike still cameras, which are used "locked off" (aimed at target and all controls locked to keep it there), video camera supports are designed (or should be) to allow the camera to be moved in almost any direction to follow the action.

Which creates a problem.

As the camera and mounting plate assembly are well above the pivot point of the head, it stands to reason that if the camera is tilted forward or backward, there will be a natural tendency for it to obey the laws of physics and keep on going due to its own weight.

Counterbalance is (usually) an inbuilt spring/ cam arrangement designed to prevent that happening.

On cheaper heads it's usually a fixed rate which is only perfect for one distinct camera weight/ centre of gravity arrangement.

Which means that if your camera system is too light, the counterbalance will tend to push the camera back to the horizontal. If it's too weak, it will still allow the camera to keep going in it's headlong fall.

If the fixed counterbalance of the LS38 is pushing the camera back to the horizontal (assuming it was correctly balanced in the first place), the camera is too light and this can be remedied by adding more weight.

If it's letting the camera fall, it's (the camera) too heavy and there isn't much you can do but chop the lens off (I jest!).

OK, now remember I'm talking TWO completely different things here:

1. Balance - the centre of gravity of the camera is aligned with the head pivot point - if the camera is placed horizontal with no locks or drag, it will stay there for ever.

2. Counterbalance - the mechanism which fights the growing wish of the camera to nose dive/ do a backward flip when pushed OFF the horizontal. If the counterbalance is perfectly matched to the camera COG, then no matter where the camera is put, it will stay there for ever WITH NO LOCKS APPLIED OR DRAG ON!

This is otherwise known as "head Nirvana" (aka the videographers friend).

So, your camera is TOO LIGHT.

A trick with the A1 (or any other cam with an external mic holder) is to find a container which just fits in the external mic holder and fill said container with lead shot (local gun store) till it's perfectly counterbalanced.

On my Vinten Vision 3, if I need to run my Sennheiser ME67 mic "off camera", I need to substitute an aluminium tube about a foot long, bungs at both ends, filled with small bolts to get the camera back into proper counterbalance.

PITA but it works.

Has that done the trick?

CS

Srinivas Swaminathan · December 6th, 2008, 11:13 PM

Thanks a ton! Everything makes perfect sense now. I'll just have to find a nice way to add weight like you have suggested. BTW, I am quite glad that it is somewhat light as opposed to being too heavy, which will mean big money down the drain.

Chris Soucy · December 6th, 2008, 11:49 PM

Hope it works out.

CS

Srinivas Swaminathan · December 20th, 2008, 08:08 PM

Quote:

Originally Posted by Chris Soucy

On my Vinten Vision 3, if I need to run my Sennheiser ME67 mic "off camera", I need to substitute an aluminium tube about a foot long, bungs at both ends, filled with small bolts to get the camera back into proper counterbalance.

PITA but it works.

Has that done the trick?

CS

This is what I have tried so far and it almost gets the job done. I need to fine tune it though to get perfection.
1. 1/2"x8" black steel pipe nipple (home depot)
2. Two 1/2" black steel caps (home depot)
3. Four AA cells. (old ones)

The whole thing costs about $4.6 and the pipe is slightly thinner for the A1 mic holder, need to wrap something to increase the thickness (3/4" pipe is too much).

Chris Soucy · December 20th, 2008, 09:21 PM

I think he's got it!

Good to see.

Thanks for letting us know, it's always good to get feedback.

CS

December 6th, 2008, 10:53 PM	#16
Chris Soucy Inner Circle Join Date: Feb 2007 Location: Fairfield, Dunedin, New Zealand Posts: 3,691 Images: 18	OooooK.................. Take 2: Quotes 1 & 2: Hmm, it's possible the LS38 camera plate is different to any other I've known and thus has a moveable VHS pin. BTW, that's a spring loaded pin designed to engage in a matching hole in the camera to stop the camera rotating on the plate. If that is the case and it can be moved, indeed, try to mount the plate as closely centered to the centre of gravity as possible, then lock it off and forget it. All further adjustments with regard to camera centering on the head should be done with moving the mounting plate/ camera assembly forward or backward in the head slot. Quote 3: OK, the reason for counterbalance. Unlike still cameras, which are used "locked off" (aimed at target and all controls locked to keep it there), video camera supports are designed (or should be) to allow the camera to be moved in almost any direction to follow the action. Which creates a problem. As the camera and mounting plate assembly are well above the pivot point of the head, it stands to reason that if the camera is tilted forward or backward, there will be a natural tendency for it to obey the laws of physics and keep on going due to its own weight. Counterbalance is (usually) an inbuilt spring/ cam arrangement designed to prevent that happening. On cheaper heads it's usually a fixed rate which is only perfect for one distinct camera weight/ centre of gravity arrangement. Which means that if your camera system is too light, the counterbalance will tend to push the camera back to the horizontal. If it's too weak, it will still allow the camera to keep going in it's headlong fall. If the fixed counterbalance of the LS38 is pushing the camera back to the horizontal (assuming it was correctly balanced in the first place), the camera is too light and this can be remedied by adding more weight. If it's letting the camera fall, it's (the camera) too heavy and there isn't much you can do but chop the lens off (I jest!). OK, now remember I'm talking TWO completely different things here: 1. Balance - the centre of gravity of the camera is aligned with the head pivot point - if the camera is placed horizontal with no locks or drag, it will stay there for ever. 2. Counterbalance - the mechanism which fights the growing wish of the camera to nose dive/ do a backward flip when pushed OFF the horizontal. If the counterbalance is perfectly matched to the camera COG, then no matter where the camera is put, it will stay there for ever WITH NO LOCKS APPLIED OR DRAG ON! This is otherwise known as "head Nirvana" (aka the videographers friend). So, your camera is TOO LIGHT. A trick with the A1 (or any other cam with an external mic holder) is to find a container which just fits in the external mic holder and fill said container with lead shot (local gun store) till it's perfectly counterbalanced. On my Vinten Vision 3, if I need to run my Sennheiser ME67 mic "off camera", I need to substitute an aluminium tube about a foot long, bungs at both ends, filled with small bolts to get the camera back into proper counterbalance. PITA but it works. Has that done the trick? CS

December 6th, 2008, 11:49 PM	#18
Chris Soucy Inner Circle Join Date: Feb 2007 Location: Fairfield, Dunedin, New Zealand Posts: 3,691 Images: 18	Glad to be of service........... Hope it works out. CS

December 20th, 2008, 09:21 PM	#20
Chris Soucy Inner Circle Join Date: Feb 2007 Location: Fairfield, Dunedin, New Zealand Posts: 3,691 Images: 18	Hey......... I think he's got it! Good to see. Thanks for letting us know, it's always good to get feedback. CS

December 6th, 2008, 11:13 PM	#17
Srinivas Swaminathan Regular Crew Join Date: Nov 2008 Location: Dallas Texas USA Posts: 33	Thanks a ton! Everything makes perfect sense now. I'll just have to find a nice way to add weight like you have suggested. BTW, I am quite glad that it is somewhat light as opposed to being too heavy, which will mean big money down the drain.