3D and steadicam movement.Not surprisingly, steadicam moves in 3D are so effective!!! In some cases it’s use really needs to be thought about story wise. In 3D you really feel the camera moving.
Which is why handheld 3D is not so great.
So that’s great right! 3D steadicam gigs for everyone! Well…..not so simple.
Unfortunately, steadicam shots usually involve someone or something close to the lens. Thus pretty much requiring the use of a beam splitter rig so the lenses can be close together.
With micro cameras…..Iconix, Cunima, LuxMedia, Si-2k and a few others you”might” be able to use a parallel setup for steadicam. Given current broadcast standards for 3D and current trends in the feature film. It most likely require a beamsplitter. It is rare you will be asked to shoot on a side by side rig on a steadicam. I have done it a few times….but none the less most of the time you will be on beamplitters……
here is a Iconix 3D rig...As small as that separation is .....many times
especially for features with a theatrical release you want to have a even smaller separation.

Beamplitter rigs are heavy….there are 2 cameras…..2 of everything! Yeah think about that for a sec!
The other main problem is their size and shape. Forget dynamic balance. All beamplitter rigs are front heavy! I mean really front heavy. Not to mention with that much weight you not going to be whip panning anyway. Also for 3D viewers whip pans might not be the best move.
Counterbalancing a 3D rig is always the biggest challenge. Being able to move your battery weight far back is crucial.
Counterbalancing all that weight while trying to maintain a shorter post requires a lot of battery weight! Or a long post….
The frequently long post your forced to go with then complicates stairs and ground clearance. Important when riding vehicles….which you do a lot with 3D steadi since it’s so heavy….dollies, camera trucks etc…
Also moving that batteries so far back can make switching all but impossible.
The “mirror box” on a beam splitter is basically a huge fucking sail! If it’s windy forget it! I’ve had a few shots ruined by a gust of wind. I mean just look at it….It’s a wind catching device!
The biggest complaint I have from steadicam operators I have worked with as a stereographer (I don’t always operate) is that it makes them look bad. The setup ends up compromising their operating so much that the director doesn’t see the challenge the operator is facing, he only looks at his monitor. This is the challenge with 3D.
Camera operating and 3D…..The operator usually is looking at a single camera view only. Usually the one that is looking thru the mirror (avoiding having to digitally flip the image and possible introduce a frame delay)
Usually the stereographer is monitoring both eyes during shooting. It's his job to worry about the 3D. Your job as stedicam operator is to listen to the stereographer and the Dp's instructions and focus on the most important task at hand....getting the frame they want and delivering smooth shots.
Just like in 2D. 3D is not different in this regard.
Since a large portion of steadicam operating involves being close to a subject, your IO distance will generally be very small....in the range of 1/4" to 1.5" at this camera separation it is acceptable for you the operator to operate from a single eye view since parallax will not be extreme and there is little chance of you occluding objects by looking at a single camera.
The only person on set that needs to see a 3D or muxed image is the "stereographer". Even then, most of the experienced stereographers are really only looking at the parallax values we see on the multiplexed image on a 3D monitor. Most of the time the experienced stereographer’s won't need to use 3D glasses.
On set 3D monitoring is more for video village people, Directors, producers, clients. The usual lot that need a pretty picture.
In general, as an operator all you want to do is keep things from the edge of the frame. Sometimes in 3D these are called “edge violations” so keep things a bit looser, no haircuts as this will give the sterographer in post production the most freedom to adjust convergence and place the screen plane where he wants.
To reiterate, concentrate on the operating. Let the stereographer monitor both eyes and worry about the 3D. It is HIS JOB.
If he see’s something that is a 3D problem like headroom, edge violations etc…..he will point them out to you and you will adjust.
I can tell you that if anything….what you will hear the most is frame looser! Which makes our lives easier.
The reason for this is that many times they will converge in post and have to scale in the image. Thus loosing the edges of frame, so by keeping things loose they are safe to adjust. I usually set framelines for this.
But basically, listen to the boss. The DP. Do what he says. If there is a 3D issue the stereographer will discuss with the DP or you. Your job is to keep things level and stable....naturally to give DP the framing he desires. In that sense, 3D is no different.
What is different is that your handling a heavy RIG!!!! that is sometimes moving on you!!!
Which brings us to my next point of conversation.
3D rig movement on your sled during a shot!
As if this wasn’t complicated enough!
What might happen during a 3D shot?
The stereographer or in some cases the “convergence puller” might “pull” convergence during a shot.
Most of the time this means (usually) one of the cameras on your rig will PIVOT on it’s axis. Meaning it will toe-in, usually if it’s a slow pull you might not feel it or easily be able to compensate. Especially after a rehearsal or the first take. This is not a huge issue.
The other adjustment that might happen is a change in lens distance…..IO “pull”. This means that the cameras will spread apart or come together……uhhh…OMFG! This is a huge shift in weight and is not something you can usually compensate for.
An example of such a shot:
…..
Long hotel hallway….actor at the end of the empty hallway.
You start from 40ft away and walk fast towards the actor while he sits there and you end up in an ECU 2’ from his face while he does his acting stuff.
Scene.
……On a dolly (where we have no balance issues) the stereographer might choose to start the shot with a 2.75” IO and pull the camera’s together so that when you end up in front of his face he is at .25” IO.
So imagine moving a 30 odd pound camera on your sled 2.5” !!!! Your post would want to flip over on you. Even if you countered with a motorized stage it would not be enough.
So how do we do this shot?
First off…..make sure your stereographer is always communicating with you when he changes any setting on the rig since frequently this causes a severe unbalance…..especially dangerous when calibrating motors.
There are a few solutions.
The easiest…..and often used on rigs with no counterbalance device. No IO pull. Done. Moving on!
The stereographer just sets a IO that will work for the whole shot and it’s a big compromise in terms of 3D but what can you do? Often this can be made to work and surprisingly less of an issue than most think. But it’s still a compromise.
The other option is for the 3D Rig to counterbalance the IO movement. There are a few ways to do this.
P+S technik FREESTYLE rig – Invented by steadicam operator Phillip Bordelais
This rig moves the opposing camera in a direct 1:1 movement of the other. One camera goes left the other goes right.
In the real world…. doesn’t work so perfect. This solution definitely improves the unbalance to the point where you can compensate and after a few takes anticipate and pull off the shot. The problem is the weight is never the same on the top and bottom camera. This results in a inherent unbalance. Also if the convergence puller doesn’t take care when he pulls he can “torque” and unbalance the rig. just like reving a big V8 at a stoplight….you will notice the whole car torque to one side. This can also happen in this kind of setup.
PACE steadirig – Used on avatar, Resident evil and others
The pace rig just like the Freestyle also counter balances the camera movement but instead of moving the whole camera like the Freestyle. It moves the rig mounting point (where your dovetail mounts.) This solution works that same as the freestyle essentially and exhibits the same problems.
Here is a detailed view of the movable camera mounting plate underneath a pace rig. Seen here on Greg Smith's rig during a movie I worked on recently. You can see the rails that the rigs slides on left to right via motors and remote control.
Prototype 3D rig I can’t talk about – I have talking with a manufacturer about a better solution and they will be coming out with it in the near future. The design should address the problems of the above methods and reduce the side effects….stay tuned.
Edited by Pedro_Guimaraes, 21 December 2010 - 01:23 AM.