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Josh Bass
01-18-2014, 01:07 PM
Hello people. Over the past year I have started to do these occasional edits where I am dealing with greenscreen/compositing. Simple talking head, sitting or standing, talking against a screen.

I would like to be able to pull better keys. Problems I'm having (not always at the same time, across different shoots) are jagged edges when matte is choked down enough for green to be gone, slight black or white outline usually around shoulders/body that can't be gotten rid of without degradation to everything else, generally edge issues.

These are shot by a professional crew with an EX-1 (sorry, not with the Ki whatever that allows 4:2:2, just the stock CODEC via SxS cards, not my call).

I've tried several keying plugins (trying to stay in FCP rather than deal with After Effects/Motion), like PHYX, Keylight, DVMatte, and Primatte RT. I've gotten OK results with all of them but zoomed at 200% I can see the issues I describe, and they're slightly visible even at 100% so I think more can be done.

I've read around and seen the advice that a) most tools will work, it's more about the methodology, and b) you generally can't get a good key in one pass/instance of a plugin; it's all about multiple instances doing different tasks, and multiple mattes composited into one.

These are (so far) corporate videos for the web/computer/intranet viewing, with tight deadlines, so I really don't want to get into multiple mattes and all that unless it's way less complicated and time consuming than it sounds. However, two passes of a keying plugin I can work with.

Can anyone advise, using the plugins mentioned above, or stock tools in FCP? Thanks. Not having luck finding really good tutorials online/youtube. One tutorial mentioned using two layers of the original video, one on bottom has the green desaturated and is combined with the keyed layer to somehow make the key better. . .not sure how to do that in FCP.

Thanks.

David Jimerson
01-18-2014, 04:37 PM
Well, obviously, it starts with how you shoot the material; better greenscreen shooting = better keys. Can we see some before/after shots?

Josh Bass
01-18-2014, 11:57 PM
I can't. Client is a mega corp and everything is super proprietary/classified, etc. Don't want it on a public forum. I assure you the material is well-shot (minus the quibble about shoot on the EX with native codec). Screen is evenly lit, talent well lit, good distance/separation between the two.



It's the edges that are mainly killing me (in terms of jaggies/roughness, not spill). By the time the key is finessed I usually get a black/blue/grey outline around subject a couple pixels wide (talking mainly head/face here), and by the time I've choked down enough on the settings to erode it, I've dug way into the talent and created aliasing issues. Softening edges/feathering/etc. usually has to be too aggressive to be useable. Just thought of something though. . .would lowering sharpness settings on cam help? EX is known for being especially sharp and we (I'm on the shoot crews) are usually on default pic profile with default sharp settings.

In addition to any tricks with any of the plugins I mentioned (using a one-pass method), what I'm trying to find is the methodology for the multiple pass method (not where you mask off different areas, but where you apply the plugin several times, once to make a rough matte, another to refine it, etc. ) I've read a few things but I'm still unclear on exactly how that works.

I realize that despite what I said before, if using After Effects or Motion can produce the best results, I could export the edited piece (source footage that is) out of FCP as a single file, composite in whichever program, then bring it back into FCP. I'd have to redo all that every time I made an edit to the original project (unless it was shortening one of the clips and nothing else), but so be it.

David W. Jones
01-19-2014, 07:53 AM
I have used all the keyers you mentioned in FCP 7, and while I haven't had issues keying for many a year, I can tell you that when I switched from FCP 7 to Premiere Pro using the built-in Ultra Key plugin, it was a huge step up from the keys I was getting before. Super super clean! You might download the Premiere Pro demo and test it for yourself.

All the Best!

Dave

Josh Bass
01-19-2014, 01:47 PM
I actually have Premiere but have only used it a few times and though I'm more familiar with it than I was, I can still move faster in FCP. Plus FCP integrates with Motion, which I'm much more familiar with than After Effects (these projects also require graphics to be created usually), so FCP's the way to go 'til I'm a Premiere superstar.

At any rate, sent my client a still of my best keying effort using Primatte RT in FCP and he says it looks fine so if it looks that way when moving, I'll go with that. Otherwise I'm going to try this 3-pass keying method I found buried in the depths of google. Seems like it would work with any keyer (it's done with After Effects/Keylight) and probably in any host/NLE:

http://www.mediagoo.co.uk/?p=202

verzap
01-19-2014, 05:15 PM
Hello people. Over the past year I have started to do these occasional edits where I am dealing with greenscreen/compositing. Simple talking head, sitting or standing, talking against a screen.

I would like to be able to pull better keys. Problems I'm having (not always at the same time, across different shoots) are jagged edges when matte is choked down enough for green to be gone, slight black or white outline usually around shoulders/body that can't be gotten rid of without degradation to everything else, generally edge issues.

These are shot by a professional crew with an EX-1 (sorry, not with the Ki whatever that allows 4:2:2, just the stock CODEC via SxS cards, not my call).

I've tried several keying plugins (trying to stay in FCP rather than deal with After Effects/Motion), like PHYX, Keylight, DVMatte, and Primatte RT. I've gotten OK results with all of them but zoomed at 200% I can see the issues I describe, and they're slightly visible even at 100% so I think more can be done.

I've read around and seen the advice that a) most tools will work, it's more about the methodology, and b) you generally can't get a good key in one pass/instance of a plugin; it's all about multiple instances doing different tasks, and multiple mattes composited into one.

These are (so far) corporate videos for the web/computer/intranet viewing, with tight deadlines, so I really don't want to get into multiple mattes and all that unless it's way less complicated and time consuming than it sounds. However, two passes of a keying plugin I can work with.

Can anyone advise, using the plugins mentioned above, or stock tools in FCP? Thanks. Not having luck finding really good tutorials online/youtube. One tutorial mentioned using two layers of the original video, one on bottom has the green desaturated and is combined with the keyed layer to somehow make the key better. . .not sure how to do that in FCP.

Thanks.

Get primatte keyer pro keyer suite from red giant software, there is even a 15 day free trial

mcgeedigital
01-19-2014, 05:43 PM
Proper lighting and and placement of the subject (ie, separation from the green screen) will solve 95% of the problems commonly associated with keying green screen.


http://youtu.be/SvV4QQT-wJ4

I also highly endorse Primatte.

Josh Bass
01-19-2014, 08:40 PM
Thanks. I've gotten decent results this time (still can't get rid of the thin outline without chopping into the hair a little) with FCP's Primatte RT and some of the PHYX filters. Primatte Pro may be amazing, but it's also the most expensive one I've researched and I really can't justify it at the moment.

To reiterate, the subject was lit well, placed well, etc. Screen was evenly lit, waveform in FCP shows flat line all the away across at 40%. I was thinking maybe reducing edge enhancement/sharpening in cam might help on the next one. This guy is wearing wearing a very light shirt, where the dark outline is most visible. I also see it's visible (when zoomed way in in FCP) in the original footage against the green! So maybe that's the answer. Didn't look at the video above but I see just from the thumbnail that the guy's wearing all black which would help hide those kinds of issues.