Better Green Screen removal

[Adooby-doobie]

Hello everyone
I have a question regarding effective green screen removal. In this tutorial: https://youtu.be/bRY66rJmlSY?si=zTquwakyQuS36XmR, at 5.51 he uses the HSL secondary colors to target the green screen. Upon selecting green he moves around the slider. Since he's wearing a blonde wig he is moving left to yellow. This point is confusing to me. Suppose, if the person has curly hair and there are green fringes after using the ultra key effect, then how should one use the colour targeting within HSL Secondary to make perfect green selections?
Please help me understand the first slider(Hue) in targeting perfect greens.

 

Thanks

[R Neil Haugen]

He's demonstrating cleaning up the outlier pixels not quite covered by the Ultra Key effect. He doesn't take the time to explain this, but that is why he goes next to the Lumetri. It's another layer of keying out the green.

So he starts to get a quick & dirty key by just hitting the green button. Which selects a bit surrounding "green" with a small feather, and all luma and saturation values on the other two key scales.

Now remember, he's trying to get the last greenish pixels shifted to something better, right? So as his key is to clean up pretty much the 'blonde' wig thing, which is yellow, he's shading towards the yellow side as that is where there's a green/yellow tinge to the hair. 

He's checking the key while doing so. This is actually pretty fiddly work, and probably could take a few minutes to really nail. I've normally needed to work with the sat and luma controls at time to get a really solid, usable result.

But that's what he's doing. Using another tool to clean up a few more pixels. And at times, one can need to layer four or five separate set tools to completely get the clean signal for use. I've also worked with mulitple layers of the Track Matte effect to pull complex keys also. Which is another subject in and of itself.