Glidecam 4000Pro Balance Keeps Shifting at DVinfo.net

Julian Frost · April 19th, 2008, 12:12 PM

Hi,

I'm new to the whole Glidecam world, but have successfully set up my Glidecam 4000 Pro and Canon XH-A1 camera. The problem is, that if I leave the camera and Glidecam set up overnight with good balance, when I come back to it the next morning, the balance is *way* off.

Any ideas why the balance keeps shifting? Everything is locked down tight.

Konrad Czystowski · April 19th, 2008, 12:19 PM

Weird. It should stay balanced. You keep everything the same? I mean LCD at the exact same position, tape inside...
And how do you leave it overnight? Standing, hanging on a c-stand or just laying it down?

Julian Frost · April 19th, 2008, 12:37 PM

Yes, everything is the same! I left the rig and camera on an old mic stand so that it was hanging vertically overnight. This morning, it wasn't vertical anymore!

Ger Griffin · April 19th, 2008, 07:18 PM

Someone mentioned this before on this forum, can't remember who right now but he had a plausible theory that graviational pull has a part to play in the balance shift over a period of a few hours +

Just thinking here- It would be intersting to see if it would be roughly back in balance at the same time the following night.

Julian Frost · April 19th, 2008, 07:36 PM

That must mean that I have it *incredibly* well balanced... :-)

Funny thing is... it's back in balance now (8 hours later). Hmmm. Very strange.

Ger Griffin · April 19th, 2008, 07:52 PM

isn't it every 8 hours the tide changes?

Julian Frost · April 19th, 2008, 10:23 PM

Could be... but I was out all day, so 8 hours after I last checked was the first opportunity I had to look at it again! :-)

R. L. Appling · April 20th, 2008, 12:28 AM

Julian - I have a 4000 on a smooth shooter rig. My camera is a HVX200. I am interested in your opinion about getting that static balance that is so elusive. Now I have been told that the heavier the rig is with the camera attached the more inertia that I have working for me in maintaining the COG and static balance. I try to keep it light for obvious reasons. What is your experience in that regard?

As far as the shifting of weight, all I can say is I remove EVERYTHING off of the camera that is not needed, I put everything that remains in exactly the same position that it would be in when I needed it. I use a quick release slide plate and a white grease pencil to mark where I place the unit when it is balanced.

Now it is possible for the unit to "settle in" but if everything is tight and remains unmoved I cant see how it would chance COG on you. Anyway, try this grease pencil idea and see if it helps. If something moves you should be able to spot it pretty fast. Best regards.

Julian Frost · April 20th, 2008, 01:05 AM

Quote:

Originally Posted by R. L. Appling

Julian - I have a 4000 on a smooth shooter rig. My camera is a HVX200. I am interested in your opinion about getting that static balance that is so elusive. Now I have been told that the heavier the rig is with the camera attached the more inertia that I have working for me in maintaining the COG and static balance. I try to keep it light for obvious reasons. What is your experience in that regard?

Well, I'm brand new to all of this... my Glidecam having arrived only yesterday, so I'm probably not the best person to ask. That said, my rig is pretty heavy as it is, and my back is complaining mightily! I have a total of 6 weights on the base plate. When I originally set it up, I had only 4, but found the rig was too light and moved off vertical too easily.

Quote:

As far as the shifting of weight, all I can say is I remove EVERYTHING off of the camera that is not needed, I put everything that remains in exactly the same position that it would be in when I needed it. I use a quick release slide plate and a white grease pencil to mark where I place the unit when it is balanced.

I have nothing attached to the camera at all. I've marked the LCD position by cutting marks into the camera's plastic LCD mount. If I align the marks, it's always in the same position! I have a quick release mount on the Head Plate too, and once I achieved static balance, I used a sharp knife and scratched into the paint at the front and rear ends of the QR plate. So far, I haven't removed the camera from the Glidecam 4000 Pro since getting it... though my internal speaker on the XH-A1 just quit, so it'll have to go down the road to Canon Irvine for repair. I'm sure when it comes back, I'll have to go through the entire re-balancing act again after they shift wires around inside!

Quote:

Now it is possible for the unit to "settle in" but if everything is tight and remains unmoved I cant see how it would chance COG on you.

I was wondering about "settling in" myself. We'll see what happens over the next few weeks or so.

I've just watched a Steadycam setup video on Youtube (http://www.youtube.com/watch?v=ns9gk...ature=related), and boy, he balanced the entire thing in about 15 seconds! The thumb screws which move the head plate forward/back and left/right REALLY make life easy... unlike the Gidecam's "pull the plate with your fingers and hope you move it enough/not too much" experience. It would be really nice to be able to modify the Head Plate so it has the same adjustment dials as the Steadycam.

By the way, take a look at my other post, tell me if you think I'm barking up the wrong tree!

http://www.dvinfo.net/conf/showthread.php?t=119788

Charles Papert · April 20th, 2008, 03:23 PM

Julian:

It doesn't surprise me much that a rig can appear to shift weight if left hanging on the gimbal for hours--there may be just enough play in the gimbal and yoke that it can settle over time to a slightly different enough position to be noticeable. I don't know if GC offers a standard docking bracket for this size rig that allows it to be hung above the gimbal/under the stage but that is the appropriate way for it to be left unattended, not from the gimbal.

Ger Griffin · April 20th, 2008, 03:36 PM

Charles, anything you have to say I'll take for gospel when it comes to these systems.
I assume since you haven't entained the theory that its not worth entertaining :)

Julian Frost · April 20th, 2008, 04:06 PM

Quote:

Originally Posted by Charles Papert

Julian:

I don't know if GC offers a standard docking bracket for this size rig that allows it to be hung above the gimbal/under the stage but that is the appropriate way for it to be left unattended, not from the gimbal.

That makes perfect sense!! I'll see what can be done about getting a suitable bracket. Thanks again.

Charles Papert · April 20th, 2008, 05:02 PM

It might be, but here's the thing--we adjust the balance of the rig every time we put it on, trimming the tilt to preset headroom for every shot, sometimes even between takes. It's a given that things will shift slightly. It's pretty much of academic interest whether the gravitational pull will affect the balance of the rig, I mean it would be sort of fun to know what it does, I guess...

Julian Frost · April 20th, 2008, 05:46 PM

Quote:

Originally Posted by Charles Papert

It might be, but here's the thing--we adjust the balance of the rig every time we put it on, trimming the tilt to preset headroom for every shot, sometimes even between takes.

I can see that would be the case. With the Steadycam brand of stabilizers, you at least have those nifty thumb-wheels for adjusting the camera balance. On the Glidecam, it's a question of loosening 8 thumb-screws and shiftin the Head and/or Mid Plates with your fingers, hoping not to overshoot! I guess you get what you pay for! I'd love to be able to replace or modify the Head and Mid Plates of my 4000 Pro so that it had a nice set of adjustment wheels!

Charles Papert · April 20th, 2008, 07:41 PM

I'm familiar with the Glidecam top stage. It's a deal killer for me personally but of course I'm used to geared adjustment knobs. It's how they've kept the cost down on that system, but it's a major flaw as far as I'm concerned--the smaller/lighter the rig, the more the need to touch up balance in a delicate fashion.

April 19th, 2008, 12:12 PM	#1
Julian Frost Major Player Join Date: Apr 2007 Location: California USA Posts: 576	Glidecam 4000Pro Balance Keeps Shifting Hi, I'm new to the whole Glidecam world, but have successfully set up my Glidecam 4000 Pro and Canon XH-A1 camera. The problem is, that if I leave the camera and Glidecam set up overnight with good balance, when I come back to it the next morning, the balance is way off. Any ideas why the balance keeps shifting? Everything is locked down tight.

April 20th, 2008, 03:23 PM	#10
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	Julian: It doesn't surprise me much that a rig can appear to shift weight if left hanging on the gimbal for hours--there may be just enough play in the gimbal and yoke that it can settle over time to a slightly different enough position to be noticeable. I don't know if GC offers a standard docking bracket for this size rig that allows it to be hung above the gimbal/under the stage but that is the appropriate way for it to be left unattended, not from the gimbal. __________________ Charles Papert www.charlespapert.com

April 20th, 2008, 05:02 PM	#13
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	It might be, but here's the thing--we adjust the balance of the rig every time we put it on, trimming the tilt to preset headroom for every shot, sometimes even between takes. It's a given that things will shift slightly. It's pretty much of academic interest whether the gravitational pull will affect the balance of the rig, I mean it would be sort of fun to know what it does, I guess... __________________ Charles Papert www.charlespapert.com

April 20th, 2008, 07:41 PM	#15
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	I'm familiar with the Glidecam top stage. It's a deal killer for me personally but of course I'm used to geared adjustment knobs. It's how they've kept the cost down on that system, but it's a major flaw as far as I'm concerned--the smaller/lighter the rig, the more the need to touch up balance in a delicate fashion. __________________ Charles Papert www.charlespapert.com

April 19th, 2008, 12:19 PM	#2
Konrad Czystowski Regular Crew Join Date: Sep 2007 Location: Burlington (Canada) Posts: 92	Weird. It should stay balanced. You keep everything the same? I mean LCD at the exact same position, tape inside... And how do you leave it overnight? Standing, hanging on a c-stand or just laying it down?

April 19th, 2008, 12:37 PM	#3
Julian Frost Major Player Join Date: Apr 2007 Location: California USA Posts: 576	Yes, everything is the same! I left the rig and camera on an old mic stand so that it was hanging vertically overnight. This morning, it wasn't vertical anymore!

April 19th, 2008, 07:18 PM	#4
Ger Griffin Major Player Join Date: May 2007 Location: Ireland Posts: 579	Someone mentioned this before on this forum, can't remember who right now but he had a plausible theory that graviational pull has a part to play in the balance shift over a period of a few hours + Just thinking here- It would be intersting to see if it would be roughly back in balance at the same time the following night.

April 19th, 2008, 07:36 PM	#5
Julian Frost Major Player Join Date: Apr 2007 Location: California USA Posts: 576	That must mean that I have it incredibly well balanced... :-) Funny thing is... it's back in balance now (8 hours later). Hmmm. Very strange.

April 19th, 2008, 07:52 PM	#6
Ger Griffin Major Player Join Date: May 2007 Location: Ireland Posts: 579	isn't it every 8 hours the tide changes?

April 19th, 2008, 10:23 PM	#7
Julian Frost Major Player Join Date: Apr 2007 Location: California USA Posts: 576	Could be... but I was out all day, so 8 hours after I last checked was the first opportunity I had to look at it again! :-)

April 20th, 2008, 12:28 AM	#8
R. L. Appling Regular Crew Join Date: Feb 2008 Location: Tehachapi, California Posts: 72	Julian - I have a 4000 on a smooth shooter rig. My camera is a HVX200. I am interested in your opinion about getting that static balance that is so elusive. Now I have been told that the heavier the rig is with the camera attached the more inertia that I have working for me in maintaining the COG and static balance. I try to keep it light for obvious reasons. What is your experience in that regard? As far as the shifting of weight, all I can say is I remove EVERYTHING off of the camera that is not needed, I put everything that remains in exactly the same position that it would be in when I needed it. I use a quick release slide plate and a white grease pencil to mark where I place the unit when it is balanced. Now it is possible for the unit to "settle in" but if everything is tight and remains unmoved I cant see how it would chance COG on you. Anyway, try this grease pencil idea and see if it helps. If something moves you should be able to spot it pretty fast. Best regards.

April 20th, 2008, 03:36 PM	#11
Ger Griffin Major Player Join Date: May 2007 Location: Ireland Posts: 579	Charles, anything you have to say I'll take for gospel when it comes to these systems. I assume since you haven't entained the theory that its not worth entertaining :)