Jerry Holway

As the guy who designed the Ultra tilt head, perhaps I can shed some insight here. Because the c.g. of various cameras are at different heights from their bases, and different cameras will weigh different amounts, there is no way to design a tilt head to tilt perfectly on the c.g. of all cameras. So I chose a pivot point that was close to the c.g. of many cameras and a variety of camera weights WHEN the rig would be in dynamic balance. I also made it with as low a profile that allowed + or - 20 degree tilting. Critical for using heavy cameras. Re-balancing statically after tilting (two seconds) restores dynamic balance - again with most cameras that usually fly on the bigger rigs. (I've demo'd this 100's of times at workshops) One alternative (using a simple tilt head) would require completely remounting the camera to maintain dynamic balance. The single most useful thing about the tilt head is maintaining dynamic balance regardless of the angle the camera takes. Try this: spin balance your rig into great dynamic balance. Then trim the rig to tilt down a few degrees (as we so often do) and spin it again. What happens? Trim it down a few more degrees. Spin again. (incidentally, it's best not to spin at a really fast rate, but that's another topic). My first shot with the tilt head was on Music of the Heart, with a normal length sled. Used the tilt head for the nominal trim. Post remains vertical. Lots of accelerations, little whip pans. Very, very controlled, very very precise. Pleasantly surprised and humbled. Also very annoyed that it wasn't instantly clear in 1988 (when we figured out dynamic balance) that the rig should have an integral tilt head. Some stuff just takes awhile to sink in. Jerry

Erwin- When you weighed the Ultra, which monitor was attached? Jerry

I like it. Thanks, Tim. Jerry

I am talking with Tiffen now to get the 1" masters and make a high quality DVD of the "Steadicam® EFP? Video Training Manual." By the way, they own the copyright on the video and on the manual that went with it, so I respectfully request that people respect the copyright. Jerry Holway

As CP went out of business three some years ago, it seems odd to me that the Non-CP category still exists. Since we have so many manufacturers of stabilizers out there, perhaps we should eliminate the category all together and keep things organized by the other topics, regardless of manufacturer. I emailed Tim Tyler about this, he suggested rightly that the users of the forum should decide what to do. Thoughts? Jerry

Interesting stuff. Some thoughts and a question: I'm very happy with the new Ultra vest which has a 100 percent rigid and very efficient front spar/over shoulder attachment and really good "cross-back" straps. I also prefer (and have) the front spar inside the waist band, like the old IIIA, II, and I vests. I only used to experience aches in my right shoulder from using a IIIA type arm when I had to lift up the sled up or push it down with much more force than the iso-elastic arm. New iso arm, no aches. Still didn't like to run with the MS vest. With both the DSD vest and the traditional vest, your body has to lean back in the vest to counter act the force of gravity on the sled. It's the same force, and the same leaning back regardless of the type of vest. Everyone who has taken a workshop with GB can remember his drawings and the "free" force required for this by leaning back. With a front mounted vest, a less than rigid design in the over-shoulder to the "Y" piece (like the Master Series vests), made for a lot more work. In a back mounted vest, the rigidity has to be in the arm attachment to the back, and from the lower back to the upper/center back). In either vest, the key is how efficient and postive your leaning is. I can only saw now that the new Ultra vest is much much better than the old MS vest, and I only get fatigued in the legs... never in the lower back, shoulders, etc. I also have much more control, less fatigue overall, can run flat out... I'd like to know how other ops with the new Ultra vest feel about it. By the way, I have been in about six different DSD vests, and some fit me well and worked well. Jerry

Phil et al- The "complete package" for the MS or Ultra does pretty well with the four batteries and a one bank charger, but in a heavy film situation things can get tricky, and what if a charger or a battery quits? I have two "quad" PAG chargers (which charge only one battery at a time, but instantly start fastcharging the next battery, giving some help to the burdened and or distracted assistants). With this charging system and only four batteries, I recently shot 9,600 ft with my Ultra, 84." LCD monitor, a Moviecam Compact, transmitting video, recording for myself, etc., in under three hours. No problem with the batteries, but I did have to keep an eye on the assistants to be sure the dead batteries were getting back to the charger, or I would have been in trouble. Mike O'Shea, who works on Third Watch, feels more comfortable with two chargers and five or six batteries. It's his comfort level. Jerry

Rob Happy new year. You got some of the physics right and some of it wrong, so I'd like to help clarify a few things... Here's a clue: the firetruck has the ladder mounted on the "front!" And I really like your pictures, because the weight (the rig) and you (the real resistance) are the same in both sets of pictures. Another big clue to what's going on. What's wrong are your force diagrams. In both cases the rig wants to do nothing more than drop straight down. The arm transfers this force to your body via the vest, and you keep the rig up, and by leaning back, you keep from falling over. All vests do two basic things. The first is to keep one end of the arm from dropping to the floor (holding up the weight). The second is enable our bodies to act like a lever above and below the attachment point so we can resist the downward force of the rig which is outside of our skeletal structure (like the firetruck example) The DSD vest enables this leverage with a rigid back, the traditional vests do it with a rigid front and straps going around to the same point in the back. The DSD vest is slightly more efficient at this task than a very well designed traditional vest such as the newer Ultra vest or the PRO vest or others, and the rigid back of the DSD vest enables this leverage much much better than a poorly designed vest - and there are many of those out there. The point of attachment does not matter. At all. Here's a clue: Think about all the work and expense to make the DSD socket block/arm attachment point rigid from the side of the vest all the way to the back. All the strength of that carbon fiber part keeps the attachment point fixed relative to the shell. The arm is actually attached to the SIDE of the shell. Another consequence of the DSD vest - and one that many operators like - is that the vest places almost all the weight carrying capacity on your hips. Traditional vests spread this out more, with the upper torso sharing some of the load. A downside of this part of the DSD vest design is that there is very little side to side torque resistance compared to a traditional design, which is why the DSD vest must be fit so carefully and so tight on the operator's hips. See the posts last year on "a strange event" (sorry no link) for another consequence of this. Hope this helps a little more... Jerry