Epic on a Technodolly

[Craig Parkes]

Thanks to the Dollyshop in Auckland and an Epic supplied by Jonathan Guest and Nick Burridge of Halcyon Entertainment NZ (http://vimeo.com/halcyonnz) we got to take out an Epic for a test shoot on the Technodolly.

A few complications (red universal mount wasn't mounting so universally on a couple of different slider dovetail plates, one Chroziel it wouldn't fit on at all, one custom made it wouldn't lock to, another (not sure whether it was custom or not) it mounted perfectly to.

Also, it seems Technodolly requires a slightly higher voltage than the sync signal sent from Epic, so we had to go with Genlock rather than shutter sync.

We were also using a really heavy lens and mattebox kindly on loan from Rocket Rentals in Auckland, which meant that we ended up having to not only weigh down the back of the camera with the quad battery mount and batteries, but also a dive weight ziptied on the back of the slider plate to get equal balance for the Technodolly head. Bit of an odd problem having a camera that was too light, but certainly easier to fix than having a camera that is too heavy!

This was all a test shoot to identify these potential issues, so while it ate into the day a bit on a paid shoot it would have all been picked up in pre-production testing, so no complaints here.

After getting around those issues we attempted quite a complicated move for a comp'd motion control shot. Lots of post work still to do of course but we were all in all very happy with the results of the onion skinning we were doing on set for previews, and are hopeful that the camera data provided out of the Technodolly will be a boon for our workflow for any post 3D additions we look to add.

Here are some photos of one very small technical marvel on top of one very large technical marvel, hopefully get to put some footage up soon.

 

[Mark Andersen]

There is the next module from Red, the "weight module" I big steel block to snap on the back of the Epic when you lenses are too heavy. Imsaynthis in jest, but when I think about it, it could be useful at times.

 

[Craig Parkes]

There is the next module from Red, the "weight module" I big steel block to snap on the back of the Epic when you lenses are too heavy. Imsaynthis in jest, but when I think about it, it could be useful at times.

We actually talked about how a weighted module might have a limited but very real market. Something designed to attach and has variable weights you can add or subtract to get balance just perfect. We were hoping the Battery Module was going to kind of work in that fashion, but the batteries and module altogether where far too light to offset both the lens and mattebox (but without the mattebox they did the job, so we weren't far off.)

 

[Brandon J. Garcia]

That thing looks like a friggin robot.
How awesome.

 

[Björn Benckert]

Looks really nice,

and are hopeful that the camera data provided out of the Technodolly will be a boon for our workflow for any post 3D additions we look to add. .

I think that you will find that using the data from the rig is possible but it's usually so much better to shoot a good tracking pass. i.e a pass with covering light and spread out tracking marks in the scene. Also it might be vice to make an extra "tracking move / take" to show the camera the scene.

Since using syntheses or such (we prefer syntheses) with a manual track (important not just go with the automatic) gives you not only a more accurate camera path it also gives you a useful point cloud of your scenery.

Using the data fed to the rig will very much show that the track is not 100% leveled, the rig is not accurate or has small vibrations, the camera is not in perfect nodal position, the lens is not accurate, etc.

So just as an advice, the data can be used for simple moves getting the VR camera about right but if you need it precise the a tracking pass is much superior.

Also for most moves it's very nice to have the camera in perfect nodal, so if possible I would slide the camera back so far so that you have no parallax shift in the lens when you pan.
Doing the the same for tilt will get you even better.

The camera position in nodal makes the rig have to move less with it's bigger parts when panning and tilting.

 

[Craig Parkes]

Looks really nice,
I think that you will find that using the data from the rig is possible but it's usually so much better to shoot a good tracking pass. i.e a pass with covering light and spread out tracking marks in the scene. Also it might be vice to make an extra "tracking move / take" to show the camera the scene.

Cheers Bjorn, I was hoping you would comment. We didn't do a specific tracking pass with added markers but we did a plate pass (both at 100 fps and 25 fps, as I wanted to have a reference of the background with better exposure/longer shutter times as we were losing light by this point)

I would think that there may be enough information in the scene for tracking to work pretty well without additional markers in this case, and it will be interesting to examine that result versus the camera data. Certainly good advice when planning a shoot where we can control things more.

The lack of controlled light is also obviously going to be a bit of a problem for the comp, as highlights outside windows etc aren't going to be in consistent and I'd prefer not to have to roto them all and replace them with the plate pass, but obviously I am able do that if I really needed to. Hopefully once I dig into the RAW I'll find an exposure level that is mostly seamless and a bit of feathering on split screen will be enough to keep the illusion going.

In terms of post production tool set for this job I am probably going to have to go with bare bones AE for Roto, which I know is probably not ideal but it's what I have the most access to and as this is a test I have not sure I can commit to buying better Roto tools at this point (the post house I work for does far more Motion Graphics than VFX work, so we don't tend to tonnes of heavy roto). Though I was thinking I might see if I can use this as an excuse to get up to speed on Mocha and figure out if that's going to be a good buy for us.

Any thoughts on better roto workflows/tools for compositing in AE would be appreciated.

 

[Patrik Forsberg]

Like Björn said, data from motion control to be used in 3d is very critical. We have a stationary set-up with a Mark Roberts Cyclop that we have been laser-calibrating on and off for the last three years, and we only got the data really satisfying last year. It is a matter of levelling and laser calibrating the tracks and all the axises on your moco time after time, eliminating compensations one after the other and ending up with real, physical data that relates to the room/studio. Just as important is quantizising and calibrating all your lenses and calibrating your ccd to be able to define the perfect nodal point at all different focus distances and apertures. Even a fraction of degree becomes centimeters with distance, resulting in sliding feet etc. That said, it can surely be done, and we are about to finish our 3rd feature film using the system getting perfect 3d fbx:s saving the time for shooting track-passes. We are averageing 20 camera position set-ups per 8h day which is pretty ok for motion control Good luck, and welcome aboard the epic moco train. And for questions, Björn is the grand ole' man, and i'll be happy to help out were I can. Attaching some pics of our 4,6 ton set-up with epic-mount. We have tried to keep the lensmount as close to Moco´s natural pivot point as possible, and have accessories and power as counter-weights. Next step will be to have Red produce a short jumper cable so that we can have only the brain in front of pivot point, and everything else behind.

Best
Patrik

 

[Craig Parkes]

That's an impressive rig Patrick, thanks for jumping in. Having talked with Marc Mateo (the TD operator) and shown him this thread I think he might jump in at some point - he's off to Cinegear at the moment. A reality with the way in which this techno dolly is going to be used means that I imagine Bjorn's advice regarding doing specific tracking passes for virtual camera data is going to be the way to go, as unlike your Cyclops setup it's going to be out in the field/in a variety of studios in differing conditions so being able to get super precise calibration is always going to be more difficult than doing a specific tracking pass.

Bjorn, did you mean Syntheyes when referring to tracking software? If so that's what we use in house as well so it's good to know we will have a comparable workflow.

 

[Johnathan Guest]

A few complications (red universal mount wasn't mounting so universally on a couple of different slider dovetail plates, one Chroziel it wouldn't fit on at all, one custom made it wouldn't lock to, another (not sure whether it was custom or not) it mounted perfectly to.

The main reason for the Red Dovetail mount not fitting onto the Chroziel seemed to be that the lock on the mount protruded too far and was caught when trying to slide it on (I'm curious if our other Red Dovetail mount will fit on it or not). The one we got it to work on was another custom dovetail plate.

Also the issue with balance was partly because we were unable to slide the rig further back on the dovetail mount because the gears for the aperture, focus and zoom were in the way. It was a very tight setup. [SUP]http://www.halcyondigital.co.nz[/SUP]

 

[Peter Strietmann]

The main reason for the Red Dovetail mount not fitting onto the Chroziel seemed to be that the lock on the mount protruded too far and was caught when trying to slide it on (I'm curious if our other Red Dovetail mount will fit on it or not). The one we got it to work on was another custom dovetail plate.

Also the issue with balance was partly because we were unable to slide the rig further back on the dovetail mount because the gears for the aperture, focus and zoom were in the way. It was a very tight setup.

Try backing out the two little screws holding down the silver plate the holds the locking lever down. Once the plate is off you can change the lever's relationship to the locking mechanism to either tighten it or loosen it. It is very simple and once the plate is off it becomes very apparent how it works.

I have some base plates that are 24" long which goes a long way to help balance longer and heavier lenses.

Hope this works.

Best, Peter