Jump to content



Photo

3D follow focus systems


  • Please log in to reply
9 replies to this topic

#1 Iain Baird

Iain Baird

    Advanced Member

  • Sustaining Members
  • 269 posts
  • Toronto

Posted 31 January 2010 - 11:41 AM

I haven't had the chance to work with 3D yet but I have seen some of the focus setups required and they looked quite a bit more extensive than the basic system. Interaxial and Convergence et. all!! The setup I saw required 2 Preston MDR's on the rig to accomplish the controls needed.

What challenges are presented with a Steadicam setup and what wireless systems being designed to independently handle the needs of 3D?

I'd love to know more about the cmotion system.
  • 0

#2 Alfeo Dixon SOC

Alfeo Dixon SOC

    Advanced Member

  • Sustaining Members
  • 756 posts
  • Atlanta

Posted 31 January 2010 - 10:17 PM

I haven't had the chance to work with 3D yet but I have seen some of the focus setups required and they looked quite a bit more extensive than the basic system. Interaxial and Convergence et. all!! The setup I saw required 2 Preston MDR's on the rig to accomplish the controls needed.

What challenges are presented with a Steadicam setup and what wireless systems being designed to independently handle the needs of 3D?

I'd love to know more about the cmotion system.

Hi Iain,

Depending on the rig you work on will dictate your needs. My last set up was a parallel rig and we only used my HU3 and MDR. I had only focus for both cameras and Run/Stop functions. If the rig has IO and convergence that need to be adjusted on the fly, then yes you will need 2 MDRs plus 2 Single Channel hand units. One for IO and the second for convergence. Your HU3 will suffice for the Iris and Focus unless the D.I.T. or DP needs a separate controller... which means you should carry the following,
1 HU3 [focus/Iris]
2 MDR [F/I/Z, primary/secondary] the primary needs a special firmware version from Preston.
1 MDR [IO/Convergence]
1 Single Channel Hand Unit
1 Micro Force

just in case:
1 MDR (backup)
1 Single Channel Hand Unit

I'm a bit curious just how many Single Channel controllers can connect to one MDR?

I've only flown a 3D setup in parallel, but if your going to adjust IO or convergence on the rig, you'll need a way to keep your horizon. One solution I've heard about was a specially built top stage that counters the IO.

I personally like the cmotion system more, but they are from across the pond and this drives the price upward with the Euro/Dollar situation. They were just about to open up a sales and service center state side. Don't know if that has happened.

-Alfeo
  • 0

#3 Iain Baird

Iain Baird

    Advanced Member

  • Sustaining Members
  • 269 posts
  • Toronto

Posted 03 February 2010 - 11:15 PM

Thanks Alfeo, very informative.

What systems look to become the norm - Parallel or IO & Convergence (Beta or VHS, HDDVD or Blueray..... etc.) or will they both end up roaming the film landscape and force us to carry more gear?!?

IAIN
  • 0

#4 Alfeo Dixon SOC

Alfeo Dixon SOC

    Advanced Member

  • Sustaining Members
  • 756 posts
  • Atlanta

Posted 05 February 2010 - 10:23 AM

What systems look to become the norm - Parallel or IO & Convergence (Beta or VHS, HDDVD or Blueray..... etc.) or will they both end up roaming the film landscape and force us to carry more gear?!?

Parallel & Prism (Mirror) can have both IO (distance between the eyes) & Convergence (angle of the eyes) by the way, but IO you can bet on with a Prism rig. Some will have neither, such as the SI2K in this PIC

I got my money on Blu-Beta!!!
  • 0

#5 Pedro Guimaraes SOC

Pedro Guimaraes SOC

    Advanced Member

  • Sustaining Members
  • 204 posts
  • Hollywood, CA

Posted 29 June 2010 - 04:09 PM

I shoot alot of 3D so I should chime in here,

Both C-motion and Preston have 3D modes in their software to sync up and calibrate FIZ, IO and convergence. Also to calibrate each lens to each other which is extremely important. I think they are still working on "mapping" functionality. Which is to match lenses to each other that might have focus scales be off fro each other. Would fix what a simple calibration could not.

also, as Alfeo described currently to achieve 3D FIZ control we need to use 2 MDR's (preston) or 2 Camin's (c-motion)

I know for that c-motion is working on a "3D camin" basically a camin with 6 inputs. Not sure if it will have 8 to include IO and conv. as well.

This would cut down the amount of cabling and stuff we need to place on 3D rigs right now.

I also know that Element Technica is developing thier own Transmitter/reciver/hand controller. Like the new c-motion the transmiter was also incorporate ALL the inputs into a single box. I saw some initial prototypes while visiting the other day. Looks like they have it together and soon it might just be one of the best systems out there for controlling 2 cameras/lenses in a 3D configuration.

So since all this stuff will end up being so specialized for 3D use, I don't think steadicam operators should worry about purchasing them. It will most likely be a function(built into the rig) or responsibility of the rig provider.

Hopefully soon this will all get alot more integrated. The "SCREEN PLANE" 3D rigs have most of the FIZ/IO electronics actually built into the aluminum frame of the rig. Thier small rig should be very steadycam friendly....especially since it tilts....like having a U2 tilt stage. THe rig is mounted on a yoke....pretty cool.



If anyone ever has any questions related to 3D let me know,

This is me prep'in a 3D rig with red cameras and a c-motion control system on a Z-Head.

You can see both the c-motion Camin's on the bottom left of the picture. Velcro'd to the mirror box with florescent tape labels...
Posted Image
  • 0

#6 Alfeo Dixon SOC

Alfeo Dixon SOC

    Advanced Member

  • Sustaining Members
  • 756 posts
  • Atlanta

Posted 29 June 2010 - 04:54 PM

Parallel & Prism (Mirror) can have both IO (distance between the eyes) & Convergence (angle of the eyes) by the way, but IO you can bet on with a Prism rig. Some will have neither, such as the SI2K in this PIC

Sorry about the dead link.... I believe this is the photo I was referencing.
Attached File  3D RIG 1.jpg   180.98KB   126 downloads


  • 0

#7 Pedro Guimaraes SOC

Pedro Guimaraes SOC

    Advanced Member

  • Sustaining Members
  • 204 posts
  • Hollywood, CA

Posted 01 July 2010 - 04:24 AM

this should be a useful link to many ..... well more for AC's since this is more their headache than the operator.

Preston PDF with 3D calibration instructions,

http://www.prestonci...Calibration.pdf



Cool picture Alfeo, but just to clarify for those looking at that pic that might get the wrong idea..... The operator will never have to wear 3D glasses especially while operating (recipe for disaster). The only person on set that needs to see a 3D image is the "stereographer"(like a 3D DOP). 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 won't need to use 3D glasses.

On set 3D monitoring is more for video village people, Directors, producers, clients (on commercials) etc...

The operator usually is looking at a single camera view only. There are some considerations you must take care about with framing etc....but that's a whole another topic on 3D operating.
  • 0

#8 Alfeo Dixon SOC

Alfeo Dixon SOC

    Advanced Member

  • Sustaining Members
  • 756 posts
  • Atlanta

Posted 01 July 2010 - 08:00 AM

Cool picture Alfeo, but just to clarify for those looking at that pic that might get the wrong idea..... The operator will never have to wear 3D glasses especially while operating (recipe for disaster). The only person on set that needs to see a 3D image is the "stereographer"(like a 3D DOP). 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 won't need to use 3D glasses.

On set 3D monitoring is more for video village people, Directors, producers, clients (on commercials) etc...

The operator usually is looking at a single camera view only. There are some considerations you must take care about with framing etc....but that's a whole another topic on 3D operating.



This was actually taken at the Maine workshop and we did fly with the Transvideo 3D View monitor (hence the ultra stylish anaglyph shades). I personally do not like to only monitor one image, but yes, it is best to only view one camera and one must decide and stick to that decision for continuity and make note if they have to switch to the other eye/camera.

I would recommend the capability to view both cameras, especially in a parallel rig because of the larger IA and convergence (if any) simply because you will have bogies in the other camera that may not show in the primary cameras field of view. My last parallel set up was two Reds and I put the two LCD's next to each other and framed up that way. On my Ultra2, I can switch back and forth from the 2 HDSDI inputs.


  • 0

#9 Pedro Guimaraes SOC

Pedro Guimaraes SOC

    Advanced Member

  • Sustaining Members
  • 204 posts
  • Hollywood, CA

Posted 02 July 2010 - 02:56 AM

Respectfully Alfeo, wearing glasses while you operate makes 100% no sense. I don't know who instructed you to do this but I can assure you it's not normal practice or helpful in any way. Besides impairing your vision for safe movement on set and giving you a headache.....operating with the glasses you are seeing the combined version of both eyes and if anything, it actually makes it so you can't see your parallax (see if your exceeding max values by getting to close to objects) and makes it hard to see if you are committing any edge violations.

80% of my current work comes working in 3D. 95% of my current steadicam income has come from operating in 3D. I have to date flown 7 different 3D rigs on my steadicam. I have also served as stereographer on 6 productions and assistant stereographer n countless others. So I am talking from experience here.

Someone, 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.

Furthermore, 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 1/2" to 1.5" at this stereobase 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 on a single camera .

Regarding parallel setups, it's much the same situation. let's take you example of 2 REDS. I have also flown this setup.

2 reds will give you a 6" IO. At this distance NOTHING should be closer to the camera than say maybe 20ft. At this distance the camera are parallel and are not converged. Anything closer will result in too much parallax and be unusable. So at the operational distance this IO dictates the parallax values in the scene will effectively be very similar to my previous example. Therefore it is not a problem to monitor one eye while operating. If you were having occluded objects in one camera, my guess is that you were just to close for the IO you had. It's the stereographers job to keep an eye on this and alert you to correct your framing on the next take.

Once again, concentrate on operating let the stereographer monitor both eyes and worry about the 3D.

Usually we use the transvideo SBL 3D on the steadicam. This lets the stereographer adjust and align the cameras before the shot. Then the op can switch to a single eye for the take, or you can leave it in anaglyph or multiplexed full color mode and monitor both eyes while you operate (with no glasses of course). Although this is misleading many times.

naturally different people work differently and there are many ways to slice a tomato....so YMMV.

Again don't worry about looking at both eyes since a large percentage of the time we never converge while shooting anyway. We shoot parallel and converge in post production. So as an operator all you want to do is keep things from the edge of the frame. Keep things a bit looser, no haircuts this will give the sterographer in post production the most freedom to adjust convergence.


Maybe it's time I make a 3D steadicam post on the general forum? where would be the best place to do that? I do have lots of photos of productions and knowledge I have no problem sharing with the community.
  • 0

#10 thomas-english

thomas-english

    Advanced Member

  • Sustaining Members
  • 1165 posts
  • UK

Posted 02 July 2010 - 04:00 AM

I am in agreement with Pedro when it comes to providing radio follow focus systems for 3D. Don't do it. Leave your Preston at home guys. 3D is such a nightmare with so much going on you really don't want to be involving yourself. Especially when the blame game starts happening just before an important shot. Its enough for you to keep this behemoth balanced on your rig with a correct supply of batteries and to be keeping an eye on where stereoscopy are placing all their boxes.

I don't wear glasses whilst shooting. what would happen if there was a RED rock about to trip up your left foot? Or even a green leprechaun running from camera right into your path. You would be blind to it!
  • 0




BOXX

SkyDreams

Wireless Video Systems

Omnishot Systems

Betz Tools for Stabilizers

Engineered Cinema Solutions

Teradek

GPI Pro Systems

Paralinx LLC

PLC - Bartech

rebotnix Technologies

IDX

Boland Communications

Media Blackout - Custom Cables and AKS

Ritter Battery

Varizoom Follow Focus

PLC Electronics Solutions