Here’s a quick test. I’ve traditionally used the chroma key when live streaming, putting the screen behind myself so I could punch out whatever messy basement might be in frame. I’ve never really used the green screen the way that Hollywood does, so this is a quick test to see about getting it right.

Relevant Websites

None! I did this all by myself (and it shows, I know)

Relevant Resources

I recorded this on my Pixel 3, standard HD (1920×1080, 30fps). The phone was mounted on a tripod so I could ensure that my clean plate and my green screen would line up after I extracted the chroma.

Technical Details

This image above is the “clean plate”. It was about 5 seconds long and sans green screen, although you can see I didn’t move it out of the way entirely. I need this because once I use the screen and remove it using Keylight, AE needs to know what’s behind there.

This is a still from the green screen segment. It was shot as a different video. I included tracking marks, but since the camera isn’t moving they weren’t really needed, but it was a good test because I later had to remove them using masks set to SUBTRACT.

Aside from tracking the marks, I used Keylight to knock out the green screen. I also used some masks: one on the left (although I could have left it alone and omitted the green screen stand in the final result), four for the tracking marks, and one at the very top because the screen frame wasn’t completely covering the frame up there. With that done, the clean plate was visible. I think I lucked out because the intersection of the chromakeyed section and the clean plate behind it are on the broad wall, so there’s no real seam to be seen.

I used a video clip from a trip to PAX East, set to 3D and angled slightly along the Y axis. The original purpose here was to create a semi-transparent virtual display that I would walk up to “check”, and that would show some of the clean plate through that as well. But I wanted to see if I could get all of this working before I went ahead and started creating a floating screen.

Scopique

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