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Green Screen keying help

DirectorX

DirectorX

Hey guys, with my entry for ITOOFC#4 (can view film here > http://www.indietalk.com/showthread.php?t=8766)

I need some help keying (to which I am new and have not been successful with).

Below is an example shot. The jpg compression makes it a little inacurate compared to the raw DV.
ally_green_dv.jpg


I uploaded a raw QuickTime DV file for anyone willing to try their hand at it.

http://www.flaviuman.com/darkness/ally_green_dv.mov
File approx. 8.5MB.
Note: The file is in DV PAL format (720x576, 25fps, millions of colors)

Looking for anyone that can do some mean keying with this footage. The backgrounds are all dark (can use black for testing).

I want to know if anything can be made out of this or if I should reshoot. This was filmed in Ohio and I have to head back to LA in a few days! Time is running out!!!

Thanks.
 
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If you can reshoot, you may as well. Never hurts.

That's a tricky one to key though, being so dulll & muted. That's the original?

If you pop it into AfterFX to key, you can add on multiple (very narrow) keys to take out what you want.

I've downloaded the file to play with... reshoot anyways, if you can.

:)
 
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Gotta agree with ZS, shoot again if you got the time, it just makes good sense.

I've never played with croma keying though I'll wager her shiny coat doesn't help. I also read somewhere you blue screen blond actors and green screen dark haired ones.
 
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The problem with your greenscreen is that it's NOT GREEN. The other problem is that your subject is wearing a reflective coat and the car has reflective material.

The color is TOO close to to the rest of the shot.


I masked it but it seems like it may not be on a tripod because there's movement, or you have EIS turned on.

Masking1.jpg



Tnis gives the best option but if she moves her head or anything like that, yer screwed. you CAN adjust the mask per frame though which will work. You'll notice that I didn't mask everything, just the main window.


This next image is keying. You'll notice that you can see the background image in the door, her jacket and all that.

keying1.jpg



Was this a GREEN SCREEN?
Did you light it separately from the rest of the scene?
Is this the raw footage or has it been color corrected or something like that?


To stop bleeding, shoot a light from the other side of the car right to the back of her head, this will help with green bleed and might give a more innocent look. Make sure the green screen is GREEN and not muted green because that mutedness is what the keyer will find in almost every other color.


The onlything I DIDN'T do here was shoot a light from the floor onto the back of the subject's head... HAIR is the hardest thing. But this is a separately lighted greenscreen (painted foam board)

VanessaGreen.jpg




Any other questions?
 
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ok, Here's what I did:

In Final Cut Express:
3 Sequences

Seq 1 - to smooth the green and amp up the color in the key
>top layer, footage with color corrector (max saturation, high mids, bump up the blacks and whites) Difference composite
>next layer, raw footage uncorrected.

Seq 2 - to pull the key and add the background
>top layer, Seq 1 with color corrector high mids Color Key tolerance 4 edge thin 78 edge feather 6 Spill Suppressor 56
>Bottom layer, Background

Seq 3 - to color grade for output
>top layer, Seq 2 with color corrector everything back down with bluish tint to it.

Result:

test_key_out.jpg


I would still recommend lighting with a rim light (pushed to the complimentary color of the screen). This would serve to separate the edges of the subject from the key more easily. Start with much brighter footage to key, well saturated...darken it later in the grading pass.
 
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DirectorX,
What are you using to key this?

I think that masking it would probably work better since the color isn't keyable...
The shot isn't that long to roto it all.

Question is... are you looking for someone to do this for you, or are you asking how to do it.

I used Combustion3 and about 15 min or less on it.

What I'm saying is, I don't think you'll have to re-shoot it. If this is the only scene, less than 2 seconds, then I'd be happy to do it fer ya.

How many VFX shots do you have/need to be done?
 
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First off, thank you all for the quick replies. I was not expeting so many thorough answers in such a short time! Thanks.

If possible, I would like someone to do the keing. All of you have done a much better job than I did.

There are 9 shots that need keying:
2:14
2:33
2:43
2:47
2:48
2:53
2:54
4:16 (2 individual shots, 1 of Ally, 1 of Sandra)
Most shots are one second in duration average.

I am aware of the poor "greenscreen" quality. I did light it separately, but the screen itself and the color are not very good.

CootDog, if you want to roto it, I can have the shot stabilized.

knightly, you're very good with the Final Cut filter. Mine didn't turn out like that :)

Shaw, that looks great. Does it look as good if you change the background to black?

I do not think I can reshoot this, and for the "hug/dissapear" shot I still have to use a green screen (I do not have access to a decent one in this timeframe).

I will export the DV files for the clips and post them.

Thanks again, guys!
 
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DirectorX: Recieved your PM and replied

Coot: Yep, Primatte it is. It isn't the straight key but I didn't spend long tweaking. As you can see there are a few places where the blue shows through. A little on the dashboard and a very little on the coat. It could certainly use more tweaking.

This was my process:

1) Apply primatte. Tweak settings.
2) Apply matte choker (comes standard with AE)

What I would normally do is mask out areas that were not going to move much or problem areas like the dashboard etc. That way I can optimize the key for the area that it will do the most good. I think part of what you are seeing is the matte choker. Without that, the key isn't as clean on the edges. Still, you have to have a good key for the choker to work and also look realistic (which I think it does fairly well in this case). Primatte really is quite powerful. You should be able to get it for combustion as it's not AE specific. I can take some screen shots of the image at each stage in the process if you would like so you can get a feel for Primatte.

As a side note, I used the JPEG above not the actual footage for this key. The footage might provide an even better key as it hasn't been recompressed.
 
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I've uploaded some more clips.

All of them will be here > http://www.flaviuman.com/darkness/dv/
(PAL DV 4x3 non-square, 25fps, 720x576)

I'll be leaving town soon, that's why this is taking me so long (packing, etc.).

The backgrounds can be replaced with black at this point (darkness). Of course, you will be credited for this.

Thanks again, everyone.
 
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DirectorX,

In case you don't already know this; be sure to set and lock your white balance when shooting green screen, and light everything well. You can always darken the video in post, after keying.

That said, if you're Mac based, you might want to try my keying software ( http://www.oakstreetsoftware.com/gkey ) ... the vector keyer is very good, and I've included many tricks and optimizations to help with low-chroma DV keying.
 
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I see how you stabelized the footage. It's a floating boarder... I should be able to do it where it's not floating... The edges would basically extend past the frame just enough to cover the floating boarder.

I've done it a few times before. It only "zooms" in just a very little bit.
 
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