Stereoscopic... Again....

massmusic

massmusic

New member
I’m working my first stereoscopic project that incorporates live action with CG. The client asked for "3D CG animation on top of the live action." They meant stereoscopic CG comped with live action.

The live action was not shot using a 3D process and will be used as a background image. If I render and deliver a stereoscopic sequence (my CG work comped over the live action) only the CG should have the 3D effect and the live action should remain flat when viewed through glasses, yes? But if I do the above and a process is used to transfer my comped sequence to make the live action 3D, What would that do to my stereoscopic CG output? Somehow I am thinking a stereoscopic of a stereoscopic, which to me should result at best, in a cancellation of the effect. At worse, something gone very wrong. Either way, I'd get the blame.

I have asked, and she doesn’t know what is going to be done with the sequence after I deliver. If I must re-render (CG only) due to ignorance on the producer’s part, I can charge accordingly. However, I'd have an ethical dilemma if I am also ignorant as to what may happen. I’d like to have her make an informed decision before I hit F10. And I'd really like to know (before hand) what would happen to my stereoscopic CG effect if the comped sequence is actually processed for live action stereoscopic.
 
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This is a pretty horrid situation indeed.
Without all the information at your finger tips its pretty hard to deliver something like this that will work.
One of the things, just from a suggestion point of view that you can do is get that BG plate into a 2.5D kind of setting by front projecting it onto geometry thats cut out and try and make it work for you in the scene and from there you can render it with the same stereoscopic camera settings as your CG material. This is probably going to look a little dodgy but if you mix it with DoF in stereoscopic it could actually be pulled off to a certain degree.
How are you are rotoscoping? Because thats going to be one of the things your going to have to do in order to pull things from the BG plate into 3D for the front projection mapping process. You may want to consider Fusion or Nuke for doing this and use its tools for stereoscopic and see what you can come up with but flat out and I will say it here, this producer screwed you by thinking the BG plates could be shot 2D and it just becomes "3D" later easily.
Sad, but I run into this kind of stuff all the time.
 
No Roto Needed

I don’t think I’m breaking any NDs by providing the following information.

The project is for a convention show opening. You have kids and adults following this “thingy” that I created in CG, to a place (also in CG) I’ll call a “garden of enlightenment” (also created in CG). The camera (being you the spectator, and I presume the other people that followed you there even though you don’t see them now) fly through to an “event horizon”. Bing, bang, boom Logo of event bursts forth and amazes the audience. Show opens.

Now, as the people move through flat land, CG stuff emanate from their feet, arms and bodies like fallen leaves, bubbles, etc. These elements, plus the garden and the logo are what I was instructed to make stereoscopic. “Make ‘em fly off the screen and hit ‘em in the eyes” is a direct quote from the convention coordinator. What I see in the BG plates indicate that while it was not shot in 3D, it sure looks as if the director expected it to end up that way. And when he gets the footage back, I don’t know if it will be further processed or what.....I made it clear that the BG plate will remain flat when I’m done. My deadline is May. I can deal with that so long as there are no full blown re-renders. I have time to do this once in house before I need to resume other things.

What I’ve decided is to provide key stills but as a sequence file as opposed to a slide show and ask the producer to treat it as if it were a final. Test it on their projection system with their glasses, but invite me to the test screening.

Media producers are all jumping on the 3D bandwagon. Chances are you will be called to work on a stereoscopic project soon. The technique is complicated enough. We need to be able to effectively communicate with our contractors so the projects come out right, reflecting our good work. The Lightwave forums are a great way for us to learn and share ideas and experiences to help make that happen.
 
Sounds pretty wild thats for sure. If you need help on the rendering side and in general working out the silly things, maybe I can assist you. I have 10 nodes here (with more on the way) all quad cores or x6 core AMD processors, with 8GB ram per box. that and I am pretty handy with fusion, and with UberCam 1.5 in the swiss army knife package, I can do a small movie out of my place these days (and I am at the moment).

Drop by www.liberty3d.com and register there on the forums and we can continue discussing there or here or over skype or whatever.

Kat
 
massmusic said:
The live action was not shot using a 3D process and will be used as a background image. If I render and deliver a stereoscopic sequence (my CG work comped over the live action) only the CG should have the 3D effect and the live action should remain flat when viewed through glasses, yes? But if I do the above and a process is used to transfer my comped sequence to make the live action 3D, What would that do to my stereoscopic CG output? Somehow I am thinking a stereoscopic of a stereoscopic, which to me should result at best, in a cancellation of the effect. At worse, something gone very wrong. Either way, I'd get the blame.

I have asked, and she doesn’t know what is going to be done with the sequence after I deliver. If I must re-render (CG only) due to ignorance on the producer’s part, I can charge accordingly. However, I'd have an ethical dilemma if I am also ignorant as to what may happen. I’d like to have her make an informed decision before I hit F10. And I'd really like to know (before hand) what would happen to my stereoscopic CG effect if the comped sequence is actually processed for live action stereoscopic.
Click to expand...
If you're delivering a stereoscopic shot then you're delivering both a LEFT and RIGHT eye image sequence (or video file if you deliver that way). So if the background is from a single eye only, it'll be the same in both of your LEFT and RIGHT eye comps which will have the affect of it being flat and "at the screen" in terms of depth. If they were to then convert the background, your CG would need to be recomped onto both eye sequences ideally with an offset relative to the scene and where you want it to sit in z-space (depth). BTW you'll need a 3D monitor or an anaglyph-capable compositor to properly tell what the depth is. Converting it WITH your CG already on would not be good or even possible without you delivering an alpha and z-depth pass to whoever is converting it. Without that info, someone will either have to roto your CG to hold it out from whatever conversion they do OR your CG will get some arbitrary "double" interocular offset which would double it's depth effect and most likely ruin the shot as "arbitrary" conversion isn't possible. You have to make depth-passes and mattes for the things in the shot in order to convert it to 3D (which is creating a LEFT and RIGHT eye from a single eye). At the very minimum you have to roto and/or key things in order to isolate them and set their depth for conversion.

This project sounds like it's being ran by people who have no idea what they're doing. Good luck.

I work on stereo shots using Lightwave and Nuke so if you have any questions, feel free to ask.
 
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