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    #21
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    It's noteworthy that there are 20 or so sizzle reels of the X-Jib, but I can't find any user reviews.

    I'd like to see how that unit pans when the head is at a 45 degree angle. Take a look at 3:29. The head does not self level, so there is going to be quite a strain on the pan motor when the crane is at high angles. It looks like there is an adjustment knob at the top that can set the angle of the head for a particular shot.

    I have to think that the unit is less than solid when telescoped out all the way. With 17 bearing points between the operator and the head, it would have to be a really special design to keep that from swaying from side to side during moves.


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    #22
    Senior Member Eric Coughlin's Avatar
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    What exactly is self leveling? When I think of it I think of the follow frame on the Seven Jib.

    https://www.longvalleyequip.com/follow_frame.php





    High end jibs like the Jimmy Jib, Cammate, Chapman, and Technocrane do not have that mechanically. From what I recall of using the Jimmy Jib many years ago you had to manually tilt up or down while booming down or up to keep your headroom the same, and it took some practice to get it just right.


    Also, what do you mean by the head panning quality? The heads the X-Jib uses are gimbals, in their case, they're primarily using Movis or Ronins, so I'd imagine the panning quality would be based on the quality of the gimbal and not the jib, unless you meant the actual jib panning, but you said "head."
    Last edited by Eric Coughlin; 11-29-2019 at 11:29 AM.


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    #23
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    What I mean regarding self leveling is that usually a jib or a crane has an arm or other mechanism that keeps the head level as the jib/crane moves up and down. You can see this arm on the opening frame in your post just above - the silver arm below the main arm keeps the platform level. Neither the X-Jib nor the Movcam crane have this. The X-jib appears to have an adjustment that allows you to set level at some tilt angle of the arm, but for all other angles of the arm, it will not be level.

    Yes, a gimbal on the jib/crane will keep the camera level. But ...

    What I mean by panning quality is that if the unit does not self level, then the panning motor of the gimbal may or may not work since it is not level. The gimbals are not intended to work with the pan axis at an angle. Take a look at 2:37 in the video with the guy in the blue suit. Note that the gimbal's pan axis is mounted at about a 15-20 degree angle. I doubt the gimbal was designed to deal with an imbalance of that sort. At that angle, the pan motor will have to fight 'uphill'.

    The Movcam does not use a gimbal. It has a regular pan/tilt system that is controlled by the operator, so as it cranes up, if the camera is looking sideways to the crane, the horizon will tilt as it goes up. You can see this at 1:46 in the Movcam video. The head mounting system is already slightly at an angle. Notice that it seems to have an adjustment knob at the top to compensate for this. I think that is also why they put the rope isolator to try to help with this. You can see that is is doing some self leveling, but it will only compensate for a bit of angle.

    The movecam does not use a gimbal. It uses gearhead motors. So it doesn't act like a gimbal. Take a look at the opening shot in this crane shot (link). See the horizon tilt as the crane goes up? The self-leveling feature was not working correctly when I took that shot. That can only be slightly corrected on the Movcam with the rope isolator. But a full tilt up of the crane will give similar results. https://www.youtube.com/watch?v=qCx0azIM1e0


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    #24
    Senior Member Eric Coughlin's Avatar
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    I guess I'm still confused. My Kessler Pocket Jib Traveler has two sections so one section is used to keep the tilt level even when boom up or down, just like the Seven Jib follow frame. Single section jibs like the Cammate, Jimmy Jib, Chapman, and Technocrane do not have this as far as I'm aware. If the high end jibs don't have it, then why is it important?

    Are you just saying gimbals are not designed to work when off balance as well as dedicated jib heads are?


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    #25
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    Quote Originally Posted by Eric Coughlin View Post
    Are you just saying gimbals are not designed to work when off balance as well as dedicated jib heads are?
    Yes, that's my assumption. I could be wrong, but I can't see otherwise.

    Quote Originally Posted by Eric Coughlin View Post
    ... Single section jibs like the Cammate, Jimmy Jib, Chapman, and Technocrane do not have this as far as I'm aware. If the high end jibs don't have it, then why is it important?
    Cammate, Jimmy Jib, Chapman, and Technocrane all have a leveling mechanism.

    Technocrane has a half-gear at the top of the head. Take a look at the opening shot and you will see the head stay level as the crane angles up - https://www.youtube.com/watch?v=q02f0bUvaw4

    Jimmy Jib uses a cable. Take a look at page 3 of the user manual - https://www.jimmyjib.com/docs/manual...tandard_4C.pdf

    Cammate uses a second bar below the main arm.

    Chapman - I can't be sure, but it looks like the cable on the right side of the crane is the self-leveling mechanism; really complicated. Chapman is awesome stuff.


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    #26
    Senior Member Run&Gun's Avatar
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    Quote Originally Posted by Eric Coughlin View Post
    I guess I'm still confused. My Kessler Pocket Jib Traveler has two sections so one section is used to keep the tilt level even when boom up or down, just like the Seven Jib follow frame. Single section jibs like the Cammate, Jimmy Jib, Chapman, and Technocrane do not have this as far as I'm aware. If the high end jibs don't have it, then why is it important?

    Are you just saying gimbals are not designed to work when off balance as well as dedicated jib heads are?
    Every decent jib(like a Jimmy Jib, etc.) I've ever been around in both the Live and Production world has had a "self leveling" mechanism for the remote head.


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    #27
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    All it takes to make a self-leveling head is a parallelogram design, or a cable or gear to imitate same. It should be a ground level basic of jib/crane design. Hearing that there are products out there that don't have this built in...sigh.

    Going beyond this, various tech exists to perform pan and/or tilt functions as one booms. The most important is auto backpan, of which the simplest version is belt-driven 1-1 compensation. You arc the crane left or right, the center turret rotates one way and the camera mount rotates the other way, keeping the camera pointed in teh same direction. Super helpful especially with a short arm. More sophisticated versions will do this electronically in both pan and tilt and can be dialed in for a given shot, so they effectively follow the subject automatically, minimizing how much work the operator needs to do. Stabilized heads will do their own version of backpan compensation as they sense their base is being rotated.
    Charles Papert
    charlespapert.com


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    #28
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    Quote Originally Posted by Eric Coughlin View Post
    It's from Austraila which means all I'd have to do is ship it to Rob Norton, then have him fly out here with it for the beer waiting in my fridge.
    I'm listening..


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