Giants of Korean Air?

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digitalskylight

Active member
Hey cinematographers,

I'm looking for some tips on green screen techniques. I was wondering how exactly Korean Air accomplished this:

http://www.youtube.com/watch?v=FEYngxOMsmg

Specifically, I'm wondering how you do green screen to make people look massive like this? Do you need to get exact camera angles (down to the degree) for both your plate and actress, would it help to have a live feed on set, and I'm assuming you should shoot at 60fps?

Another note: I've heard from some professionals it might be best to even shoot on a bright white backdrop to key it out and avoid spill. Thoughts?
 
Simply answered, yes. Somebody had to either know or accurately calculate through geometry the lens angle, focal length and height of the touched up photographic plate image (might even be CG originated) and then recreate that upon the women, of course based on the ideal size they are to be. Calculating the women to the size they are supposed to represent, such as 50ft or 100ft tall. It's all about perspective.

As far as keying... green screen can be used just fine. If you are on a big enough stage, you'll most likely A) be using a good amount of light, say t/5.6 shooting stop which will overpower any sort of bounce back from the screen, which B) shouldn't be an issue, as greenscreen lighting is very even and should bd separated enough from the talent to not have reflected light spill back that far. With that said, any chroma or luma key could probably work so long as the wardrobe doesn't conflict a great deal.

A live composite can help match actions and etc, sure. Slow motion I suppose is an aesthetic choice. I don't think it is necessary to make the composite work, BUT I do think that it helps convey mass and size. The women moving in slow motion can add a weight and scale to their 'size'.
 
Awesome Patrick. Thanks for your help! Now, I was just wondering- is it enough to know that I'm shooting say a 45-degree angle of the lens at 50mm and an f/5.6 for both the plate and the model, or should I be gathering more info about one or the other?

Ryan Patrick O'Hara said:
Simply answered, yes. Somebody had to either know or accurately calculate through geometry the lens angle, focal length and height of the touched up photographic plate image (might even be CG originated) and then recreate that upon the women, of course based on the ideal size they are to be. Calculating the women to the size they are supposed to represent, such as 50ft or 100ft tall. It's all about perspective.

As far as keying... green screen can be used just fine. If you are on a big enough stage, you'll most likely A) be using a good amount of light, say t/5.6 shooting stop which will overpower any sort of bounce back from the screen, which B) shouldn't be an issue, as greenscreen lighting is very even and should bd separated enough from the talent to not have reflected light spill back that far. With that said, any chroma or luma key could probably work so long as the wardrobe doesn't conflict a great deal.

A live composite can help match actions and etc, sure. Slow motion I suppose is an aesthetic choice. I don't think it is necessary to make the composite work, BUT I do think that it helps convey mass and size. The women moving in slow motion can add a weight and scale to their 'size'.
Click to expand...
 
For Vfx camera reports, you should know the height of the camera from the center of the lens (aka nodal point), tilt angle of camera, lens focal length, lens aperture, distance from camera to subject, and other factors. Those are the basics. This is what you would need to make the two shots match up, BUT this commercial has different requirements since you are not going to composite the woman into the plate using the real world data you gathered since she will be larger than her actual self. You would need to take into account the desired height of the woman and change the math accordingly. It's geometry. Funny how I used to wonder how that had anything to do with film-making when I was in high school.
 
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