using a white background for compositing

HI,

We're shooting a commercial video for the internet and the director wants to use a white background (cyc) with an interview subject. She would like me to pull a matte from this and composite some images behind the subject during the interview.

I'm familiar with a green screen in this instance but not a white one. How does one pull a white matte, especially if the subject may also have some white in them? I know I can use the luma traveling matte but I'm afraid of drop off in the subject.

Any advice about how to do this in FCP?

Thanks,
rachel

Green screen, or blue screen, but only if there are lots of plants/subjects wearing green. You don't want to pull a luma key on close ups. There are whites in a person's eyes, teeth are white, speculars will be a tough area to do a luma key too.



www.strypesinpost.com

Thanks.

The director insisted on a white cyc, so that's what we're dealing with. I'll just have to do the best I can. Any other advice on how to mitigate the damage would be really welcome.

Rachel

We used to do this a lot in the old linear digital online suites. Cropping the luma key to the talent's ear kept the eyes and teeth from keying out. Sometimes the hands would take extra TLC if the talent gestured into the text-area.

It can be done...whether easily or not in FCP I can't say from experience, however.

Might ask for a test-shoot to try the built-in FCP filters and/or to see if you should try a third-party filter, if no one offers a proven solution.

debe

thanks!!

If you know of any good third party filters for this , shoot me a message. unfortunately, I'm not getting a test shoot on this one. I guess this is the test shoot. Oy.

rachel

>The director insisted on a white cyc

Well, not much you can do there, but hope and pray that the talent is a perfect stone.

Rotoscoping in FCP will leave you banging your head on the desk. Meanwhile, you may start looking into one of these:

[www.silhouettefx.com]

and if budget allows, get a good motion graphics artist..



www.strypesinpost.com

I think Ripple Training or DV Creators had a tutorial on this using a White Screen. For the life of me I cant find it. Sure, it an be done. The problem here is white shirt in front of a white screen. Same problem if green shirt in front of a green screen.

Michael Horton
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The director insisted on a white cyc, so that's what we're dealing with.

I ran into a Director like that once...he was an idiot too. Nobody shoots white screen to intentionally pull a key from it - too many issues. Plan on multiple garbage mattes & rotoscoping. I would not dream of doing it in FCP (AE for sure using Keylight and a few select masks).

When life gives you dilemmas...make dilemmanade.

I would do a garbage matte, crank the smooth up, and bring the opacity down to half -- perhaps it's a certain effect the director is looking for. I've done similar - but I wouldn't call it a "key".

Better still tell thee director that a white background is done with color background (green or blue mainly) White is the stream (layer) used to make it look like if it was shot on a white cyc only with better results.
Even if you didn't have to add other images that is how you do it best. Otherwise you have to deal with over exposure around the model.

God Bless,

Douglas Villalba
director/cinematographer/editor
Miami, Florida

[www.DouglasVillalba.info]
[www.youtube.com]
[vimeo.com]

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The director insisted on a white cyc, so that's what we're dealing with.

I love people like that. It just adds to the days I'm on the project. More business.



Andy

in the end she decided NOT to use the white cyc. Yay! Thanks for all the great answers!

Just to add a little clarity here, for the record.

If what you want is to have actors on a white background, you'll get far better results by shooting on a white cyc than by shooting greenscreen and keying them out.

On the other hand, if you want actors on a white background with stuff composited in behind them, you'll get much better results by shooting greenscreen.

If you want a white background with stuff but the stuff doesn't interact with the talent at all ? it never goes behind them, in other words ? just shoot on a white cyc and then do ordinary compositing on top of that.

Different techniques for producing different results, y'know?

I partially agree if it is not full body. If you need to get full body with pure white with no shadows then you need to overexpose by at least 2 f-stops (reflected measuring) wish results in a halo of light around the actor. This is even more evident with light color hair and cloth.

One thing is for sure, It is a lot less work to do it on a white cyc.

This is just me playing around my newly build cyc with just the white primer before I painted it green.
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[url=http://web.me.com/douglasvillalba/Advertising-Villa/Video_Equipment.html#4]http://web.me.com/douglasvillalba/Advertising-Villa/Video_Equipment.html#4[/url]

God Bless,

Douglas Villalba
director/cinematographer/editor
Miami, Florida

[url]http://www.DouglasVillalba.info[/url]
[url]https://www.youtube.com/user/douglasVillalba[/url]
[url]https://vimeo.com/douglasvillalba[/url]