Additive Keying with tracking marks

I have a green screen iPhone shot to comp. Minimal movement and some thumb scrolling over the screen and tracker marks.
I used the additive key technique for my comp (first time trying after learning about it). Initial key looks great.
My challenge comes with the blue tracking markers they turned on in the green screen app.
What are some ways around this you have taken? I’m figuring the answer might be roto, but hoping there might be a better solve.

One quick thing to try is get a key/matte of the tracker marks then pixel spread stretch contract till they’re filled with the surrounding screen texture. (Use an iterative pixel spread chain for best results).

Or just any other way to zap the markers. Whatever it is, use that as your add key source.

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I think your best best is removing them and restoring the hand where it goes over them before you do the additive keying process. But- bear with me here because huge chance this won’t necessarily work- if you could get a nice enough key on that blue color and enough separation chroma wise from the fingers, could you maybe make them the same color of green using using a sampled colour source from the phone green screen and setting to photoshop color blend mode or just cc’ing if you’d like. Then do your additive keyer process, just using what you’re getting as your soft key fill and then filing it in with your hard key? I love to imagine this would work! I am really not confident it would because it just seems too obvious in a way- making the blue tracking markers green- ya know? Id be prepared to do some roto- mixing of keys- etc.

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I thought about this too @GPM - my first thought being an infill blur or pixel spread, which would work great, UNTIL the fingers passed over the tracking markers and you just get like a mushy skin meets green screen kind of strange color blob.

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I think you’ll need to treat it like a separate pre-comp, and the creative brief on the pre-comp is “remove the trackers.” However you’d normally get rid of something. Then that pre-comp is your add source.

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Yeah yeah, I think we’re on the same page here. I think some roto, mixing of keys to get those fingers back over top is going to be inevitable, no matter what.

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I guess the other info that would be helpful is, when saying additive keying, how exactly are you going about it?

I always paint them out first.

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Sampling the blue and shifting it to green with the colorwarper might also be a possible way

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As John said, where they cross over fgd detail, I have always found the best method is painting them out, I have tried other techniques, such as colour warping, keying them, however theres always an issue with the edges of them, which eventually will need to be painted.

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Stabilize the phone, paint them out.

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Thank you all so much for the replies!

Sounds like painting and roto might be the best bet. I tried the pixel blur and it works great, then gets weird where the finger crosses. keying the blue and shifting to green was close, but I kept getting hard edges from those markers when I color shifted.

@GPM, your comment about treating the trackers as it’s own creative brief makes a lot of sense and a good approach to thinking about it.

I think I’ll attack it as a lot have mentioned, some paint, some roto, maybe a little color warp, then I will have a clean source to key from.

@BrittCiampa i was going the route of Joel Osis’ additive keyer hack.

Thank you all again for sharing your knowledge!

Top tip…if you use the Image node and use Selectives as your matte for blurring/A2Beauty/(possibly!) Infill Blur, it doesn’t necessary include stuff you don’t wanna include.

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Out of interest were the tracking markers of any use to you at all. Did you use them? Hmmm i bet not.

I my experience, if they’re in shot, then no use at all, but if there aren’t any, you sure wish there were!

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I used them since they were there, but honestly I probably would have gotten a good track without them too.
If they didn’t put them in I’m sure it would have been shot way worst and I would have wished for them, haha

Big fan of additive keying for screens. I provide a green screen for the screen with green trackers of a slightly different green to the green background. Then they (usually) key out and don’t need to be painted, but they still work for tracking. Having them there also means that editorial can get a decent track for the offline which helps smooth their progress along as well.

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I was half consulted before they shot. I knew they were doing the green screen app, but really wish they picked the lighter green for the track marks and not blue (and black for finger swipes)

when you are saying use selective for the the matte with the image node, would that be pipping in a matte from another node? For instance if I got a nice key from the blue markers? or would I do that color select with the image node?

I haven’t used the image node much, but have watched some of grant’s videos on it and seem to remember you can do selective color there. (I probably should rewatch them, the image node seems so deep when I get into it).

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Yes and yes. Try performing an A2Beauty in Image using a Selective, whether created inside or outside the Image node and fed externally. And be amazed.

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