Virtual Reality

After a post I made about the virtual studio at New Broadcasting House I thought I'd create a topic dedicated to some of the clever technology behind it.

http://yfrog.com/scaled/landing/860/icpes.jpg
Image from Matt F on Twitter

Whilst I know how it works, I still find it a very clever technology that's surprisingly analog in its setup. With "barcodes" fixed to the lighting grid the position of the camera in 3D space can be matched to the virtual camera and thus the background added over the green. The ability to do the same for a jib mounted camera, meaning both X, Y, Z, and Zoom data is needed in real time to match the shots.. Clever stuff indeed!

One thing I always wonder is how the problem of reflections could be overcome. Obviously, ITV News has partly solved the problem by working out that, due to the perspective, only the desk needs to be reflected (virtually), and not the presenters. However, it does break the illusion on the rare occassions when they've walked onto the shiny floor and had no reflection.

Perhaps there will be software solutions in the future, but I wonder whether it would be possible (in technical terms, not necessarily in cost terms) to have some sort of one-way mirror floor, where from above it's green enough to key, but is see through enough from below to provide a reflection, through some sort of robotic camera that can mirror movements up top, as it were.

I doubt it would be a cost-effective solution to the problem for news production.

Why are the yellow panels done in VR?

I remember it being something to do with the yellow being too close to green in colour to guarantee it isn't keyed out - possibly it's for colour matching reasons.

Thinking about it, the panels are meant to be shiny. I would imagine shiny yellow panels would be problematic, especially at close angles (akin to the glitch that occurs anyway).

Because from the cameras point of view yellow is made up of green and is similar. The Ultimatte hardware could struggle with the key otherwise, actually easier to key it yellow.

Surely a mirrored floor surface would reflect the presenter and the green background?

...but i imagine that simply painting the floor with a high gloss grey, with the occasional green rectangle would replicate the current virtual floor quite well. The only issue would be where the virtual floor joins the real floor, but a creative redesign of the floor would eliviate this.

I'd love to know their reasoning behind building this virtual set in the first place. That studio looks like it has ample space to build a real version of the virtual set they have, and would look far better.

By a one-way mirror, I don't mean that it would reflect anything - I meant the idea of one side being green and the other side clear. I couldn't think of a better way of describing it.

Apologies if my imagination has run away with me, but if i've understood you correctly...

You are suggesting the whole set be raised up and placed on top of a one-way mirror, so the green screen studio looks identical from above the mirror, but a Duplicate camera position which exactly mirrors the position of the real camera is positioned below to capture the "reflection" of the presenter and then the whole image is comped together.

That is very convoluted.

Even if cost were no object as you say, technically it would be far easier to use a normal mirror floor that reflected both the presenter and the green backdrop, that way, keying is easy, the presenter's reflection is present, and the only issues would be to alter the presenter's reflection to match the reflective properties of the CGI floor, whether that be through a CG component or some sort of semi transparent vinyl applied to the reflective surface to assist... but that just brings me back to high gloss paint, which would have the same effect. Any green that did leak through in reflection would be keyed with the reflected backdrop.

Yes. But it'd be cool.


You could have a strong, highly reflective surface that emitted/reflected/absorbed infrared in such a way that the reflection could be altered in the CG properly - otherwise, the reflection and the presenter wouldn't be seperable.

I hadn't realised how many simple shots in TV and movies were done with CSO and some VR type techniques (although in post production rather than live) because it's easier to shoot in a studio.

It amazed me when i saw this on behind the scenes DVD extras a few years back.

It seems its entirely due to the expense of moving the entire production to the real location for the few shots needed for the episode. Its often easier, as you say, just to send a small Visual Effects or 2nd Unit team out to the location to get the shots first and then add in the actors and sound, on a green set. It also allows them to avoid scheduling issues where a location is unusable, or the dreaded weather.

Visual effects have got so good now that most viewers simply wont be able to tell where the real ends and fake begins.