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Green screen recommendations

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Oleksandr Kocherhin
Green screen recommendations
on Jul 31, 2020 at 12:12:00 pm

Hi guys, I'm suffering with Greenscreen already several months. So I would appreciate any recommendations.
As you can see on the right side there is a spill on the head and arm.
My setup:
- 2 daylight bulbs (45 W CFL-Daylight) with umbrellas for subject 45 degree left and right.
- I also tried with and without 2 softboxes (45w CLF-Daylight) to light greenscreen. From what I see the greenscreen is not perfectly lit.
- Greenscreen is 2 meters behind the subject
- I key it in Final cut pro
- My camera is Sony 5100 f1.4, iso 100, 25 fps, shutter 1/50, 1080p

The main problem is that I don't know what I need to adjust. Is it the greenscreen than should be lit better or something else? Do I need more light or should it be dimmable?

Video with background:






Raw video with greenscreen:






Greenscreen image:
https://drive.google.com/file/d/1KZdV6WTNAfeuzzjkMhnL9iOdWnfFtKDw/view?usp=...

Greenscreen Problems image:
https://drive.google.com/file/d/1x0IBozaoU2gDFQAEjZrIu8tVWpi03fBz/view?usp=...

Greenscreen Problems image 2:
https://drive.google.com/file/d/1Nh647wrV_kERR3y4bW6GSNcog8mG5yiA/view?usp=...

Keyed out image:
https://drive.google.com/file/d/1jSKZrsVYpdE3i1dxLuJRz81eD2_G_N3F/view?usp=...

Keyed out with sample color removal:
https://drive.google.com/file/d/1mTYnjIKM1dLBTb5gmfaI42EG-lcF5Fx0/view?usp=...

White/black image:
https://drive.google.com/file/d/1ptEZh4vhIYX9SRQgbEROqfkybv4TD7GD/view?usp=...

While/black with sample color removal:
https://drive.google.com/file/d/1dk9yFot721I2bY8lz90wJmZcp0evjLF5/view?usp=...


Also I tried adding 2 softboxes on the bottom. It helped with colors on the bottom of the screen but not with spill.







Here is the last try. I used the harsh 80v lamp without umbrella in my face and from my point of view picture looks much better.







Image of my lamps setup:
https://drive.google.com/file/d/1wbaEKtbYzrkyiCIDsgt7fbNSsOBMZKGY/view?usp=...

I also bought magenta 1/4 gel for back light but it didn't arrive yet.

I'm open for any suggestions. Thanks for your time.


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Todd Terry
Re: Green screen recommendations
on Jul 31, 2020 at 3:35:03 pm
Last Edited By Todd Terry on Jul 31, 2020 at 3:38:36 pm

Actually, I think your key isn't too bad... in fact I'd say it's as good or better than 90% of the ones you see online.

The lighting on your screen is not quite perfectly even, but I don't think that's the problem and your setup looks pretty acceptable to me. I did a quick key test without even doing any adjustments or tweaking, and it looks pretty good to me...



I wasn't keying the way you did, though, I was in Premiere and just threw on the Ultra Key filter and that's what I got.



I'm going to suggest that rather than trying to tweak on your setup too much more (although you certainly can), you need to tweak on your keying parameters and settings. Now I'm not an Apple guy so I know zero about Final Cut and what all you can adjust there... but I'm sure it is similar to what I can do in Premiere. Just play with all your settings one at a time (in Ultra Key I can adjust transparency, highlight, shadow, tolerance, pedestal, choke, soften, contrast, midpoint, desaturate, range, spill, luma, saturation, hue, luminance) and see if you can get it to improve. I bet you can.

Also, actually while I was reading your post I said to myself "He should try a bit of magenta on the backlight" but then I got to your very last line and see you have some on order. That may help you with spill if you are getting any green fringing around the edges.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



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Oleksandr Kocherhin
Re: Green screen recommendations
on Jul 31, 2020 at 4:29:27 pm

Hi Todd, thanks for your comment! Your reply brought back the hope that it's not that bad.
Sure Final Cut has mostly the same settings as Premier Pro matte, spill reduction, etc. I will try to play with settings in post then.
One last question. Does the last try looks better? Before it was 2 umbrellas 45 angle to subject and now it's just a harsh light for the subject without umbrella in the middle.

Before
https://drive.google.com/file/d/1wpjpC1C2s9B6FkMVY-Ph14Z0ECJXk90O/view?usp=...
After
https://drive.google.com/file/d/1qlwGjhh2p8rmKjcDrMRTiasNT-KUoPi-/view?usp=...


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Todd Terry
Re: Green screen recommendations
on Jul 31, 2020 at 5:03:16 pm

Eh, Oleksandr, it's hard to say, the difference is really almost negligible.

If forced to say, I would say the "Before" pic has slightly better lighting on the subject, but the "After" pic has a slightly cleaner key. It's really only the tiniest of differences, though.

I really think your keys are pretty clean. I'd really say you're getting to the point where you are worrying over something that you and only you see... to everyone else it will look fine. That is natural, of course, we all see our own flaws much more than anyone else does. But for web-type videos I think they are perfectly fine, good job actually... I've definitely seen much worse.

If anything, I'd say crank way up the backlight, if you are using one (or hair light, or rim light, or whatever you choose to call it). That is usually the most neglected instrument in a lot of lighting plots. I always tell people to look at the wide shot on a national talk show when the talent is standing on stage. Invariably the talent's shadow will be in front of him or her... not behind. That lets us know they are using a very bright backlight. that will also help you, not only by giving a little highlight on the top of the hair and shoulders to give you separation from the background, but might make your key cleaner as well.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



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Oleksandr Kocherhin
Re: Green screen recommendations
on Jul 31, 2020 at 5:05:25 pm

Thank you so much Todd, I really appreciate your help!


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Mark Suszko
Re: Green screen recommendations
on Aug 3, 2020 at 8:48:42 pm

What I find with a lot of people starting out in green screen keying is, they throw the shots into the keyer without first grading them, and that's a recipe for trouble. Your first step in editing the key is to color balance the footage against an actual scope (turn on scopes in FCPX).

When I shoot greenscreen I bring a MacBeth color chip chart along to shoot thru the lens; built-in camera bars don't relate to the actual scene and lighting. Bring a color bar chart to the next shoot and you'll see a huge difference when you adjust to that reference in post.

Get the whites at 100 and the blacks at zero or seven point five IRE units. Adjust the mid-tones until they look good and still retain detail. Look at the saturation and skin tone ranges. I like my greenscreens to peak at around 80-90 IRE and be well-saturated. Saturation is actually more important than brightness but evenness is most important over all.

Only now are you ready to try the keyer.

FCPX does have additional greenscreen tools in it. You'll want to play with light wrap settings and the greenscreen compensation which applies an artificial magenta backlight - that works, sometimes.

I'm unaware of what you're shooting on, but in the FCPX inspector, make sure you have "spacial conform" set to "none". Now you're working with the full native pixels you shot.


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Oleksandr Kocherhin
Re: Green screen recommendations
on Aug 3, 2020 at 8:53:11 pm

Thanks a lot Mark Suszko, I will check and try everything that you mentioned. Yes I just threw the keyer and waited for the nice results :). I will study FCP and things you mentioned. Can you recommend any links or videos were people are doing such things?


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Mark Suszko
Re: Green screen recommendations
on Aug 3, 2020 at 9:05:40 pm

My friend Larry Jordan does a lot of specific FCPX tutorials online, including on good keying. You can find some of his lessons free online; others, available inexpensively at Larry's web site. Others here will probably mention additional video tutorials they like as well.


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