Steadicam Zephyr shake?

[Eric Fletcher S.O.C.]

A few things

 

Dynamic balance won't cause camera shake and if you are using Jerrys method of dynamic balancing it's not surprising that you are having an issue getting in DB. Do a forum search for my method, it works EVERYTIME and takes less than 60 seconds to achieve.

 

What you are seeing is either a Post vibration or a stage vibration. Check to see that your stage is tight, your post to stage connection is tight, your center post isn't "Ringing" and check your arm to socket block interface since that will transmit vibrations to the gimbal/centerpost on every step

[Brent Johnson]

I had this problem with a red camera once. I figured it was because the camera was front heavy, and I had move the whole thing back on the sled. The RED didn't have a beefy Arri style dovetail, so I only had the thin aluminum from the Zephyr's dovetail holding the camera up. Every little, minute movement was, of course, amplified.

 

So if you had the RED dovetail, how would you have attached the Camera to the sled? Because I had the same problem while Oping the RED as well.

 

@Mark I'm going to check all hex nut connections and components that shouldn't be moving at all. And I'll post up what I have been using when I get the chance.

 

@Eric What do you mean by "ringing'? And what should I be looking for with the socket block interference?

 

Thanks guys, I really don't want to send the rig back!

[Brent Johnson]

 

 

So here's the set up with wireless FF and a V-lock batt. on top of the stage. Any problems with it? And take note of the extra weight that I'm using. There's two rubber washers with stainless washers in between them to not damage the camera/dovetail.

Edited February 1, 2012 by Brent Johnson

[Eric Fletcher S.O.C.]

Umm wow, hate to say it but that's NOT the way you want to build the rig the rubber washers are your first issue...

 

You never want the gimbal that low unless you are in a superpost situation.

 

You want to camera as close to the stage as possible

 

Get rid of all those rods and condense the masses to increase ridgity

[Brent Johnson]

How high do you want the gimble from the top of the post? Also, how do I mount the Wireless ff and battery to the top stage if I don't have rods? I'm glad I'm showing these pictures! I really need to get my ass to the training course. Sadly, this is my last post for today until 11:23pm says the forum. There's a countdown for how many posts you have per day I guess, and my limit is ten or so. I'll be on tomorrow morn!

[Brian Freesh]

Generally one would want the gimbal and the camera lens to be as close as possible to each other, farther from the gimbal, the more a bad horizon will be visible in frame. Here you've raised the camera so far off the stage, in turn forcing you to lower the gimbal for balance, double whammy!

 

10-1 your entire rod set-up is flexing the one point it is mounted to, causing the vibration, or at least the lion's share.

 

You are right that you need rods for focus, but as you can see from your footage, you also need a far more rigid setup. Figure out how to get the rods as low as possible, braced in at least two places. the battery is also likely flexing because it is mounted by one point far off from it's CG. Secure that too. The camera unfortunately only has one place to secure it. There are cages out there that undoubtedly help them be secure. In absence of that I always use a rod set up with enough surface area to really connect with the bottom of the DSLR. I then shim it with Gaff tape and crank the screw on there. I usually rip off the rubber pad on the bottom of the camera at the end of the day because of this. Thems the brakes with those cameras. I reaffix it and it seems to be fine.

 

There is so much in that picture potentially causing your vibrations. Get a solid, rigid setup, and then do another test.

[Twojay Dhillon]

Easy fix, although not cheap: get two cheese plates from RedRock Micro along with two 15mm iris rod clamps (they come with two thick shims, each). I believe the above is available as a kit from CES out of Burbank, right off the I5. Then, you'll be using the iris rods (I usually use 18" rods for this setup) to essentially hold the two cheese plates in alignment, plus the RedRock Micro's DSLR mount clips onto the 15mm iris rods.

 

Then, you'll want to secure the two cheese plates to a common surface. Since I fly a bigger rig this is a no-brainer for me as I attach all DSLR setups to a weight cage/plate system. Should you not have one, Janice Arthur can build you one to your dimensions (first calculate your total load: camera, lens -- the heaviest one you use -- follow-focus system, battery, cables, cheese plates, iris rod clamps, shims, DSLR mount, iris rods, sled, monitor, batteries, i.e. THE WORKS), then figure out the total load capacity of your arm and have a plate made that will keep the total weight under the total carrying capacity of arm (by a good margin. . . say 15-20%, if possible).

 

As a further piece of advice, I would build the entire shebang and then take it to whomever is building/fabricating your plate (seriously, go with Janice, I hear nothing but great things about her stuff), so that they can look at the spacing of the holes on your cheeseplates in order to take the guesswork out of where, exactly, to place the holes (which will further be tapped/countersunk) which you will use to affix your dovetail, which will then mount into your topstage.

 

Boom. You have a system that has dropped your c.g. significantly, provided a large, flat, stable, common mounting-surface, and also added a bit of weight, thereby enabling you to get your gimbal up and lose the non-operator-induced shake.

 

Hope this helps. I can take pics of my setup tomorrow.

[Wolfgang Troescher]

I have a little problem with my setup, too: Got a weight plate from Janice. On the weight plate I want to fix my baseplate with 15mm rods. My Problem: The distance between the rods and the weight plate is too small to fix the motor of my follow focos system (HocusFocus), so I have to increase the distance. My little strange workaround can you see on the picture.

 

So I´m looking for a baseplate which leaves enough room between rods and the plate. What do you think about this product or this product from Zacuto?

 

 

 

Wolfgang

[Twojay Dhillon]

My response to your inquiry is identical to the OP's; it is 2 posts up!

 

Get the right stuff the first time: the most surface area plus the most stable platform. The only thing that I really don't like about the RedRock Micro system is the DSLR mount, which I am having my machinist come up with a work-around (Sal from Cinematic Precision).

 

I shall post pics when I have that piece available. But it will be compatible with the system I described in the post above.

 

 

 

I have a little problem with my setup, too: Got a weight plate from Janice. On the weight plate I want to fix my baseplate with 15mm rods. My Problem: The distance between the rods and the weight plate is too small to fix the motor of my follow focos system (HocusFocus), so I have to increase the distance. My little strange workaround can you see on the picture.

 

So I´m looking for a baseplate which leaves enough room between rods and the plate. What do you think about this product from Zacuto?

 

Wolfgang

[Brian Freesh]

Wolfgang,

 

Rather than move your camera higher than the plate, move it forward. This will leave you plenty of room behind the camera to mount other things, like the receiver for your motor. See the attached photo for an example.

[Wolfgang Troescher]

Wolfgang,

 

Rather than move your camera higher than the plate, move it forward. This will leave you plenty of room behind the camera to mount other things, like the receiver for your motor. See the attached photo for an example.

 

Hi Brian,

 

your photo would be very interesting :rolleyes:

[Eric Fletcher S.O.C.]

Rather than move your camera higher than the plate, move it forward.

 

 

Thats valid to a point. One of the issues with DSLR's is that the overall polar moment is VERY short and that screws on getting the "Film" plane close to the center post. As you move the film plane away from the center post your pans become arcs and that will amplify any Pan "wag" you might have

[Twojay Dhillon]

Just looked at Wolfgang's pic again, and it appears his height issues can be solved by merely switching from that egregiously large knob to a Kipp handle.

 

Or am I being misled by the pic's angle?

[Carl Wiedemann]

Brent,

 

You may want to get a 15mm dogbone to achieve the proper spacing with your motor, rather than trying to use a riser to accommodate the distance of the motor. http://www.cinewidgets.com/

With the flexibility the dogbone allows you can use a baseplate with more surface area rather than a riser.

http://store.zacuto.com/universal-baseplate-v3-includes-12-inch-rods.html

or

http://store.zacuto.com/Mini-Baseplate.html

 

And reemphasizing some of Eric's suggestions: try to find a means to balance the sled with the gimbal closer to the stage. Basic operation (horizon control) will be more difficult with the gimbal near the center of the post.

 

Ditch the rubber washers and try some gaffers tape if you want to reduce slipping and protect gear.

[Wan Zhong Wei]

The stage is shaking because your 15mm rod attachment holder is simply not strong enough, and you have too many items causing much stress on the rods.

 

try to remove the rods and place the camera directly onto the weightplate. and see what happens.

 

i have a similar problem with a 5d2 and pilot rig. i used the red rock micro dslr platform holder thingy, it was like an earthquake, i swapped to a normal baseplate, is fine already :)

 

the folks have explained that the cheeseplate will help also. so maybe you can give it a try.