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Jutter while shooting Steadicam

Jim Coulter

Jim Coulter

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I'm noticing a 'jutter' on sections of Steadicam shots particularly where I am flying and panning at the same time. It's almost as though the frame is shaking but not all the time...very intermittent. I have a ticket open on it with RED. I have already uploaded 2 R3D files- one shot at 23.98/ 1/48 at 4K and the other at 29.97 1/60 4K

This is not the same phenomena that you get when panning very fast at 24 fps

This is very prominent and shows up consistently in Steadicam shots. I don;t notice it when shooting from a tripod. I'll let you all know more when I hear back from Red Support.
 
Are you sure it doesn't occur all the time ? Frame skipping is more obvious on steadicam shots because you're in perpetual movement. Check every frame with a digital slate on your tripod shots.

Check also all your cables, connections & batteries : fast movements on a steadicam could make some micro-cuts in your connections.
 
Also - what mount and lenses are you using? If You have the Canon mount and using IS stabilized lenses - this might be the cause as well. The internal gyros can stabilize only to certain degree of shake and if you cross that - you will get a "sudden" jump (shake). Try changing the IS setting - or simply add proper gyro-stabilization to your entire rig. Adding the Gyro stabilization will help even if You are not using IS lenses...

Peter
 
Peter Majtan said:
Also - what mount and lenses are you using? If You have the Canon mount and using IS stabilized lenses - this might be the cause as well. The internal gyros can stabilize only to certain degree of shake and if you cross that - you will get a "sudden" jump (shake). Try changing the IS setting - or simply add proper gyro-stabilization to your entire rig. Adding the Gyro stabilization will help even if You are not using IS lenses...

Peter
Click to expand...

You're perfectly right but I would disable ANY lense stabilisation while using a steadicam system.
 
I've seen this with steadicam models that are top balancing, where the stage is and balance trims happen at the top. There are models that trim at the bottom. I've seen it fixed by using a wooden clothes peg to jam into the space between the stage and post.
 
HI guys,

Thanks for the input. I am not using Canon lenses- I am using an 18mm Red Pro Prime. The Steadicam is a Zephyr and I am shooting 23.98, 4K at 180 degree shutter. I did tests with a Wooden Camera fastback and Switchtronix V-mount battery and I also did tests with a Redvolt in the side handle- same result.

As far as 'frame skipping' I'm not sure. When you say shooting a digital slate- do you mean from a tripod with no movement to find out if it's skipping frames? What should I be looking for?- a new unique frame number from the timecode slate for every frame?

I would be very surprised if this 'jutter' is coming from a sudden jump or shake as the test run was pretty straightforward. Once around the cars and mailbox and back. I could see it as I walked past the house (on the walls) then it was smooth as I passed the cars then I saw it again as I flew past the mailbox rather quickly and the once again as I approached the house (seeing it on the walls)
 
would be interesting to see how it looks because I think I've seen the same behaviour flying EX1 @ 720/60p, still don't know the cause, but on scarlet I tried all possible frame rates with moderate speed of motion and even 24fps is butter smooth;
 
You can see some of what I'm referring to there but I actually have a better sample without the girl walking. The eye tends to focus on her and not the jutter. I will upload and post the link here. It will be a 720 Pro res Quicktime from RCX

Does this look normal to you?
 
i see some jitter, but to me it looks more like a vimeo compression artifact of converting 24 to 30p, all web content hosting sites convert everything to 30P,
so I wouldn't shoot 24 for web, but does it look the same when you play original clip?
 
yeah, it doesn't look like an artifact, more like a mounting top plate is shaky, and if it's not,
save the log send it to RED,
but strange, ah?
 
Yeah, it appears you're dealing with a rigidity issue on the Steadicam itself. Check all your physicall connections for any looseness in screws/plates. Do the same test on level ground where you can remove large steps and check your balance/horizon with a bubble level before operating to get the weight of the setup over itself vertically. A loaded up epic will push the boundaries of your sled so it's important to have everything set correctly.

Practice! Do the same move 10 times over, watch your operating horizon, and be conscious of your footwork. See if the jitter is in every shot when the camera moves, then you might be onto something wrong with you camera, but based on the video, it's specifically related to your setup and operating. Not trying to bash you, just speaking from experience as a young operator who has had similar issues.
 
Steadicam Problem was solved

Steadicam Problem was solved

It turns out the issue was a third party V-mount battery plate. Even though I was not using it to power the Scarlet- I still had it plugged in. Apparently the thing was acting like an antenna- perhaps the cable is not shielded properly. But we moved it to an Epic and flew it along the same path and voila! The issue was there on the Epic as well. Once we removed it from both cameras it resolved the problem.
 
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