UltraKey issue…fuzzy edges

[Jeff Pulera]

I don’t see it as an issue of arm hair – the shirt edge is very clean on the shoulders, but under the arms/sides, the shirt edge is as bad as the inner arm, so I’d say it is a problem with a dark/shadow edge in that area – lack of separation/definition from the background.

Change the lighting to get more light into that area, possibly even from behind.

If you can possibly capture as 4:2:2 rather than camera-native 4:2:0, that extra color resolution will help to get cleaner edges. One way to do that would be to use an outboard recorder such as one from Atomos, or record live output straight to computer using a Black Magic capture device. Besides 4:2:2 color, the video is far less compressed also, just all-around better for keying.

Thanks

Jeff Pulera
Safe Harbor Computers

[Steve Brame]

Ultra Key is fighting with the difference in luminance between the top right corner of the screen and the bottom left, causing you to have to ‘over-key’ or possibly choke too heavily. Pretty wide variance between the two areas.

Certainly reshooting with more even lighting on the green screen will help, especially if you can capture a better color space as Jeff recommended. Lacking the ability to reshoot, you could try duplicating the video track, then key the top track to the brighter portion of the screen while keying the lower track to the darker portion. Then mask out the lower portion of the top layer so that the two layers blend at their seam. After Effects may be a better tool for that.

And, as I usually recommend when keying difficult footage, The Super Tight Junk Matte tutorial.

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“98% of all computer issues can be solved by simply pressing ‘F1’.”
Steve Brame
creative illusions Productions

[Benjamin Cohen]

Thanks everyone. So your suggestion a better lit key, more even for next time?

[Steve Brame]

Absolutely. The better the lighting job at the shoot, the less work you have to do in post.

Asus P6X58D Premium * Core i7 950 * 24GB RAM * nVidia GeForce GTX 770 * Windows 7 Premium 64bit * System Drive – WD Caviar Black 500GB * 2nd Drive(Pagefile, Previews) – WD Velociraptor 10K drive 600GB * Media Drive – 2TB RAID0 (4 – WD Caviar Black 500GB drive) * Matrox MX02 Mini * Adobe CC * QuickTime 7.7.5
——————————————-
“98% of all computer issues can be solved by simply pressing ‘F1’.”
Steve Brame
creative illusions Productions