We have three cameras outputing 1080i/50 to Aximmetry, following usual keying procedure (Advanced B w/cleanplates, adjusting mainly High & Low Cut), yet every single one of the compositgion resulting thin white outline for bright things such as skins and bright clothings.
Keyer Creat White Outline
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That being said, one of our three cameras manage to feed us stable 1080p/30 input.
Sadly, there is no improment:
@MS-Barry: Yeah, definitely don’t use interlaced! Try sorting out the flickering or go down to 1080p25/30.
The white outline happens in the camera. It’s probably a result of a combination of things:
1. Too bright or over lit green screen, resulting in too much spill. If you can’t keep a big distance to the screen you should use a darker green screen color like chroma green and not the digital green variant.
2. 4:2:2 color subsampling will always cause edge issues. Best way to avoid it is to use 4K capable cameras since it will hide the issue, especially if your final output is 1080p. You’ll still get better results with 1080p signals if set Aximmetry to render in 4K internally (in project settings).
3. In-camera sharpening should be avoided at all costs. Apply it post key in the Adjuster panel instead. The built in Aximmetry sharpener is great, especially if you render at 4K.
4. Your keyer settings look way off! If your screen is properly lit and you’re using Clean Plate, the High and Low cut should be at around 0.2 and 90 at the most.
If you’re still stuck you can hire me for an hour or two to troubleshoot your setup remotely.
Hi Twenty Studio,
Thanks for the in depth explaination. We tried applying 1080p to all of our inputs and output, and two of our camera flicker like the video shown above, it is unusable, do you know possible reason?
Thank you
The flickering could be caused by a number of things. What capture card are you using? Does it flicker in other applications as well? It could be something as simple as bad SDI cables or something in your signal chain that can’t handles the bandwidth of 1080p.
Hi TwentyStudios and Evgesha
Sorry for get back to you late, We've done some more testing.
We are usung AJA kona 4, the system also flickers in Pixotope (they advise us to use 1080i).
Our SDI cables function properly, we tried them with different machine that run Reality by Zero Density, all stable.
Cameras feed output as HDMI, convert to SDI, and into our AJA KONA 4.
The one camera that can feed us 1080p still have the same problem - the very visible white outline. It doesn't seems to be a interlaced or progressive issue...
The Camera Focus Distance does nothing, we change it manually and it change nothing about the scene, not even blur anything.
We also tried changing our keying, like Eric suggested.
When Keyer module its defualt values, though the key is bad, there are little visible white outlines. When we start to change them to ideal values, the outlines really start to pop-up.
Hmmm.... might be an odd assumption, but is there any chance that the keyed signal is not post-multiplied by Alpha?
Normally this would lead to dark outlines, but I ran into situations in Axy where white outlines appeared.
'Odd' because the built-in keyer normally handles post-multiply correctly as long as one doesn't mess around too much in the compound itself... :-)
PS: Regarding the flicker this definitely looks as if some incoming signal is borked.
From my point of view it's not related to Axy but to some sort of [odd signal conversion|bad cables|mismatched camera/converter settings|...]
@MS-Barry: Did you try everything I suggested?
Set Aximmetry to render in 4K internally.
Set High Cut and Low Cut properly.
Turn off all in-camera sharpening.
Check that your green and foreground are exposed properly. Lower the amount of light applied to the green.
After setting Aximmetry to render in 4K, try playing with the Edge Color correction parameter and enable Remove Highlights.
What camera models are you using? Can you post a raw, full resolution capture of your camera output using the Recorder module? Set it to .png and capture a single frame.
Post a screenshot of your Keyer settings.
The Camera Focus Distance is not related to this, but it should definitely be able to blur the background so address this as a separate issue.
Hi.
To me this looks like artifacts from the keying process.
In the second image, the area between his fingers is probably green, but the built-in despill makes them look white.
Is there a reason you're using interlaced footage?
Interlaced basically gives you only 1/2 the vertical resolution to pull a good key from....
I would suggest going 1080/p50 (or even p25) and look at the Matte output of the keying module while adjusting your settings.
Cheers & all the best.
Eric.