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Old September 26th, 2004, 12:04 PM   #31
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<<(Ever meet an overweight steadicam operator?).>>

Err, yeah, actually! I can think of several off the bat. They are still strong guys nevertheless. (I could stand to lose a few pounds myself, Dan!)

It's true that we are not fans of being used as a human dolly ("the dolly that bleeds", as Steadicam pioneer Ted Churchill used to say), and there are a number of directors, especially in TV, who feel that they are saving time by using us as such. What sometimes happens is that a deceptively simple shot that seems like it would be easy on the dolly is assigned to Steadicam, and then it begins to take a life of its own and ultimately becomes a true Steadicam shot (and sometimes, if it stays on the dolly, it ends up being an entirely different shot which would be hard or impossible to replicate on Steadicam). That's the best case scenario. Unfortunately I've shot a lot of lockoffs also.

Dan, could you actually qualify your point about the gimbal again? My comment was a misunderstanding from the original post; I thought the angle that was being discussed was the orientation of the gimbal handle to the post as viewed vertically, which would change if the wrist is tilted, for example. In subsequent posts I understood that we were actually discussing the rotation of the gimbal around the post in the pan axis. That being the case, the effects of a lopsided gimbal will manifest the same if the handle is rotated or if the camera is panned.

For example, imagine that you are following someone from behind. The gimbal handle is as described earlier at around 30 to 45 degrees to the right (let's use clock face: 4 o'clock). Now we are required to accelerate and come up on their right side and shoot them in profile. Most likely we will still be facing forwards, but the rig has panned 90 degrees to the left, effectively locating the gimbal at 7 o'clock. And now, we accelerate some more and get in front of the actor as they break into a run. Unless you have the agility to run backwards at top speed, chances are you are forced into "Don Juan" and your gimbal is now at 10 o'clock.

But again, this is no different than panning the camera 90 degrees and then another 90 degrees.
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Old September 26th, 2004, 04:02 PM   #32
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I think I see the confusion as I am now confused a little. I balance the rig with the camera 'panned' 30-45 degrees to the right from the handle.

With the mounting plate and the adjustment screws, it is a little different from a standard rig, but it is also cheaper. It can even fly it for short periods hand off it I need something. But pan it 180 and it tilts. Maybe I will mount my VX on it soon and see if it is different. My Sony consumer cam just is funky to balance.

BTW, I saw someone with a 4000 this summer with the weighted part side to side and not front to back. ? Could not talk to him to see if was a decision to do it or just misunderstood the directions. I did not get to see him use it either.
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Old September 26th, 2004, 06:01 PM   #33
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Charles wrote:
" ...Err, yeah, actually! I can think of several off the bat. They are still strong guys nevertheless. (I could stand to lose a few pounds myself, Dan!)"

Hey, that's muscle, not Fat, Charles! Every steadicam op that I've seen that's been at it for a while has legs like freakin' tree trunks.

"...It's true that we are not fans of being used as a human dolly ("the dolly that bleeds", as Steadicam pioneer Ted Churchill used to say), and there are a number of directors, especially in TV, who feel that they are saving time by using us as such. What sometimes happens is that a deceptively simple shot that seems like it would be easy on the dolly is assigned to Steadicam, and then it begins to take a life of its own and ultimately becomes a true Steadicam shot (and sometimes, if it stays on the dolly, it ends up being an entirely different shot which would be hard or impossible to replicate on Steadicam). That's the best case scenario. Unfortunately I've shot a lot of lockoffs also."

That's the nature of the beast, isn't it? It's along the same lines as that old adage: "The job expands to the time allowed". The job expands to the equipment you have on hand. I was an editor for years, and always appreciated a decisive director.

"...Dan, could you actually qualify your point about the gimbal again? My comment was a misunderstanding from the original post; I thought the angle that was being discussed was the orientation of the gimbal handle to the post as viewed vertically, which would change if the wrist is tilted, for example."

I understood the posts as people trying to balance the thing in the first place. So if you were looking straight down from the top of the rig, the angle of the handle would be pointing slightly right if you were right handed. Off to the left for a left hander. On my design, the handle itself has bearings, and comes straight out from the gimbal, so no matter what the wrist did, it wouldn't effect the unit or the balance at all. I never understood the "static" handles on commercial units like the glidecam. Fatigue sets in that much quicker, and if you twist your wrist, the gimbal is no longer on the same plane! (as you pointed out).

"...In subsequent posts I understood that we were actually discussing the rotation of the gimbal around the post in the pan axis. That being the case, the effects of a lopsided gimbal will manifest the same if the handle is rotated or if the camera is panned."

I think that is absolutely true. A lop-sided gimbal would throw everything off. That's why bearings in the handle are so important.

"...For example, imagine that you are following someone from behind. The gimbal handle is as described earlier at around 30 to 45 degrees to the right (let's use clock face: 4 o'clock). Now we are required to accelerate and come up on their right side and shoot them in profile. Most likely we will still be facing forwards, but the rig has panned 90 degrees to the left, effectively locating the gimbal at 7 o'clock. And now, we accelerate some more and get in front of the actor as they break into a run. Unless you have the agility to run backwards at top speed, chances are you are forced into "Don Juan" and your gimbal is now at 10 o'clock."

Once the rig is balanced, none of this will make any difference--even it the camera has the LCD screen open. You can spin the thing 360 degrees if you want. (Don Juan's are a bit tricky with the hand-held units). But when BALANCING, the handle has to angle off a bit on the hand-held units. Once it is balanced, the handle is always pointing the same place in relation to the center post, eventhough you are panning the camera. It really screws with your head, because the CAMERA is no longer in the same position. Yet, balancing it like this works. At least on my design. Of course, this wouldn't apply to rigs like the steadicam Jr where the handle is basically a universal joint.

I'm working on a vest/arm unit for Volume II of my book. I'll have to bring it by so you can have a look when it's done (still working on the iso-elastic arm mechanism). Seems you have a lot of experience with the real steadicam.

Hope this post made sense!

Dan
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Old September 27th, 2004, 08:59 AM   #34
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I finally got around to looking at the GC website, and light is beginning to dawn in my cobwebby brain. Am I understanding that the GC 4000 gimbal has a two-axis gimbal? This would explain the issues described here, but I'm a bit baffled how it achieves isolation without that third axis bearing in the handle itself. Or am I not seeing something in this picture?
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Old September 27th, 2004, 10:10 AM   #35
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The handle rotates around the bolt attached to the arm and does s/s. The arm attaches bearing and does up/down. The bearing does the pan.
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Old September 27th, 2004, 11:00 AM   #36
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Hi Charles,

That's exactly my point about the glidecam. There ARE NO bearings in the handle. And if there were, they would have to mount it differently to the gimbal, more like a real steadicam. To me, Glidecam really missed the boat, and I can't for the life of me why they designed the handle like this. Cost is really minimal to do it "right" so there must be some other reason I haven't discovered.

Check out the photo on my site. Maybe that will clear things up:

http://www.dvcamerarigs.com/Stabilizer.html

So you have 3 axis points: the gimbal itself, the bracket that attaches to the gimbal, and the bearings in the handle. Sure, mine doesn't look as pretty, but I think it works much better!

Dan
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Old September 27th, 2004, 10:32 PM   #37
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Sorry, George, not following your description. I know this stuff is a bit difficult to describe.

Dan, I'm hearing you and I am still trying to understand how this can possibly work (obviously I'm pretty familiar with the classic Steadicam gimbal). Without that bearing in the handle, and by holding the handle at, say, 45 degrees (or 3 o'clock), this means that you can't the tilt the rig without tilting the handle also??! And that if you pan 90 degrees to the left, you can tilt but there is now no isolation in the roll axis? Ugh!

Apologies, but I can't make out enough detail in the gimbal on your site (love the graphics!) to understand exactly what the design is like, but I'm glad you get the importance of a three-axis design.

Harkening back to something George asked about earlier:

<<BTW, I saw someone with a 4000 this summer with the weighted part side to side and not front to back. ? Could not talk to him to see if was a decision to do it or just misunderstood the directions. I did not get to see him use it either.>>

This is actually a pretty good idea, as long as it doesn't bang into the legs and prevent one from being able to pan. It will give you added inertia in the roll axis, which is usually a problem area for most operators (that's what makes the photography look "floaty"). You are giving up some inertia in the tilt axis, but that is generally less of a problem. Except for this non-gimballed tilt thing! Jeez...

To understand this, one must think of the physics of the stabilizer; it creates inertia (steadiness) by spreading out the masses. The further from the center of gravity, the more inertia.Picture the rig with the lens facing sideways: you have a camera that is perhaps a foot wide, and a base that is about the same. That is the mass you are moving through space when tilting. Now turn that rig 90 degress, so that you are looking directly down the lens. You now have a mass that is only a few inches wide (as is the base). That's the mass that is affected by the roll axis. By turning the base sideways, you are increasing the inertia, rather like a tightrope walker's pole.

And with that, after having humped a Panaflex around a filthy industrial basement all day on a martial arts movie (with David Carradine, still around!), I'm off to the showers.
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Old September 28th, 2004, 08:23 AM   #38
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I shot a music video this weekend - and used the 4000 in some of the shots. Footage turned out pretty good... once i get the final product, I'll post a link...
Thanks for your help!

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Old September 28th, 2004, 06:31 PM   #39
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I'm slightly confused as to how some of you are coming to certain conclusions, but i'll just give the official answers anyway....

The gimbal on the 4000 Pro is 3-axis, not 2. And each axis has its own set of BEARINGS.
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Old September 28th, 2004, 06:44 PM   #40
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The operation of the gimbal as well as balancing information can be found by going to the "Videos" page on Glidecam.com

http://www.glidecam.com/demo.html

For example, take a look at "The Stability of Balance" for the basics behind balancing these things, and the "2000 Pro in operation" which illustrates the range of movement in the gimbal. These are excerpts from Glidecam's Demo DVD.

The audio didnt translate horribly well, but should be sufficient. I'll be remastering them soon for better web viewing.
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Old September 28th, 2004, 09:16 PM   #41
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Thanks for the clarification, Casey. I couldn't for the life of me imagine how the GC 4000 could have only two axes of movement. I've played with it at trades shows and figured I couldn't have missed that.
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Old November 9th, 2004, 04:32 PM   #42
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Thread Necromancy!

Ok I just got my GlideCam 4000 Pro in. I'm using an XL1s sans viewfinder/mic. I also have a Marshall L4 monitor with sunshade and external battery pack attached to it.

I find it IMPOSSIBLE to get anything more than .8-1 second drop time from horizontal to vertical position. What am I doing wrong? I assumed that it needs more top heavy weight to have a slow drop time. So I took all but one weight off of each side and it STILL dropped in 1 second or under.

I'm guessing the monitor is adding too much weight to give it a slow drop time but I need some serious horizontal balance b/c this thing swings back and forth way way too much. The vertical balance is ok but if I walk and then stop it just starts swinging too much.


Any pointers?
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Old November 9th, 2004, 06:27 PM   #43
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I found that the key for me was to make the thing as bottom heavy as possible... then fine tuning would smooth out any imbalances.
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Old November 9th, 2004, 06:40 PM   #44
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Zach...

It's important to balance the sled with the right drop time. Otherwise there's a tendency to act like a pendulum with every acceleration or deceleration.

A good example of that is a baton held at one end. Every movement of your hand will tend to swing the baton.

However, hold that baton in the middle, just above the balance point, and the tendency to swing each time you move forward or back is greatly reduced.

Same holds true for any camera stabilization system.

If the sled is too bottom heavy, you'll have to add weights to the top or shift the gimbal to a lower point along the column. At least that's how it works on the V-16.

Put the mic and viewfinder back on. That will add some mass high on the sled. Also, you'll need the viewfinder to provide critical exposure information as zebras will not be displayed on an external monitor.

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Old November 9th, 2004, 08:36 PM   #45
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... Well... not TOOO bottom heavy.... I use the drop test mentioned in this thread as well... if the rig is top heavy (and mine is pretty heavy - xl-1 with marshall monitor) then imbalances will really be pronounced. As soon as you hold it in one hand it'll go flying. By making it a bit bottom heavy then these imbalances are slower to develop and you can resolve via fine tuning....
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